# Boeing Alert Service Bulletin MD11-78A017: Revision 1

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### Page 1

Commercial 
Airplanes
MD11
Service Bulletin
ALERT
Number: MD11-78A017
Original Issue: December 04, 2023
ATA System: 7800 7834 7151
SUBJECT: ENGINE EXHAUST - Thrust Reverser - Thrust Reverser Wire Harnesses Inspection
and Test
EXPORT CONTROLLED - This technology or software is subject to the U.S. Export Administration Regulations
(EAR), (15 C.F.R. Parts 730-774). No authorization from the U.S. Department of Commerce is required for
export, re-export, in-country transfer, or access EXCEPT to country group E:1 or E:2 countries/persons per
Supp.1 to Part 740 of the EAR.
9E991ECCN:
BOEING PROPRIETARY
Copyright © 2023 The Boeing Company
Treatment of this document and its content is governed by contract with Boeing. Rights to use this document
are licensed on a per aircraft basis and such rights may not be transferable. For more information, contact The
Boeing Company.
Boeing, the Boeing signature, the Boeing symbol, 707, 717, 727, 737, 747, 757, 767, 777, 787, Dreamliner,
BBJ, DC-8, DC-9, DC-10, KC-10, KC-46, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8, Poseidon and
Boeing liveries are all trademarks owned by The Boeing Company; and no trademark license is granted in
connection with this document unless provided in writing by Boeing.
Original Issue: December 04, 2023
MD11-78A017
1 of 201
5.0

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### Page 3

Table of Contents
S u m m a r y  ...................................................... 5
1. PLANNING INFORMATION ........................................ 9
A . E f f e c t i v i t y  ................................................ 9
1. Airplanes ............................................. 9
2 . S p a r e s  A f f e c t e d  ........................................ 1 0
B. Concurrent Requirements ...................................... 1 0
C. Reason ................................................ 1 0
D. Description .............................................. 1 1
E. Compliance .............................................. 1 1
F . A p p r o v a l  ............................................... 2 7
G. Manpower .............................................. 2 7
H. Weight and Balance Changes .................................... 2 9
I. Electrical Load Data ......................................... 2 9
J . R e f e r e n c e s  .............................................. 2 9
1. Existing Data: ......................................... 2 9
2. Data Supplied with this Service Bulletin: ........................... 2 9
3. Installation Drawings Used in the Preparation of this Service Bulletin: ........... 2 9
4 . P r o c e s s  D a t a :  ......................................... 2 9
K. Publications Affected ........................................ 2 9
L. Interchangeability and Intermixability of Parts ........................... 3 0
M. Software Accomplishment Summary ................................ 3 0
2. MATERIAL INFORMATION ........................................ 3 1
A. Material - Price and Availability ................................... 3 1
B. Industry Support Information .................................... 3 1
C. Parts Necessary for Each Airplane ................................. 3 1
1 . K i t s / P a r t s :  ........................................... 3 1
2. Parts and Materials Supplied by the Operator: ........................ 3 1
3. Parts Modified and Reidentified: ............................... 3 2
4. Parts Removed and Not Replaced: .............................. 3 2
D. Parts Necessary to Change Spares ................................. 3 2
E. Special Tooling - Price and Availability ............................... 3 2
F. Special Tooling Necessary to do this Service Bulletin ....................... 3 2
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 3 3
A. GENERAL INFORMATION ..................................... 3 3
B. WORK INSTRUCTIONS ....................................... 3 5
FIGURE 1: ENGINE 1 PYLON - PRECOOLER INSTALLED PYLON WIRE HARNESSES - INSPECTION
.................................................. 7 3
FIGURE 2: ENGINE 2 PYLON - PRECOOLER INSTALLED PYLON WIRE HARNESSES - INSPECTION
.................................................. 8 3
FIGURE 3: ENGINE 3 PYLON - PRECOOLER INSTALLED PYLON WIRE HARNESSES - INSPECTION
.................................................. 9 0
FIGURE 4: ENGINE 1 PYLON - PRECOOLER REMOVED PYLON WIRE HARNESSES - INSPECTION
................................................. 1 0 0
FIGURE 5: ENGINE 2 PYLON - PRECOOLER REMOVED PYLON WIRE HARNESSES - INSPECTION
................................................. 1 1 0
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### Page 4

FIGURE 6: ENGINE 3 PYLON - PRECOOLER REMOVED PYLON WIRE HARNESSES - INSPECTION
................................................. 1 1 8
FIGURE 7: ENGINE 1 PYLON AND ENGINE 3 PYLON - JUNCTION BOX ELECTRICAL CONNECTORS
- DISCONNECTION ..................................... 1 2 8
FIGURE 8: ENGINE 1 PYLON AND ENGINE 3 PYLON - JUNCTION BOX - REMOVAL ....... 1 3 1
FIGURE 9: ENGINE 2 PYLON - JUNCTION BOX ELECTRICAL CONNECTORS - DISCONNECTION . 135
FIGURE 10: ENGINE 2 PYLON - JUNCTION BOX - REMOVAL ..................... 1 3 7
FIGURE 11: BENCHWORK - JUNCTION BOX COVER - REMOVAL .................. 1 4 0
FIGURE 12: BENCHWORK - JUNCTION BOX - INSPECTION ..................... 1 4 2
FIGURE 13: BENCHWORK - JUNCTION BOX COVER - INSPECTION ................ 1 4 4
FIGURE 14: BENCHWORK - JUNCTION BOX COVER - INSTALLATION ............... 1 4 6
FIGURE 15: BENCHWORK - JUNCTION BOX COVER - REPLACEMENT ............... 1 4 8
FIGURE 16: ENGINE 1 PYLON AND ENGINE 3 PYLON - JUNCTION BOX - INSTALLATION .... 1 5 0
FIGURE 17: ENGINE 2 PYLON - JUNCTION BOX - INSTALLATION .................. 1 5 4
FIGURE 18: ENGINE - LEFT SIDE AND RIGHT SIDE THRUST REVERSER ELECTRICAL HARNESS -
INSPECTION ......................................... 1 5 7
FIGURE 19: ENGINE - RIGHT SIDE THRUST REVERSER ELECTRICAL HARNESS - REPLACEMENT
................................................. 1 5 9
FIGURE 20: ENGINE - LEFT SIDE THRUST REVERSER ELECTRICAL HARNESS - REPLACEMENT . 161
FIGURE 21: ENGINE 1 AND ENGINE 3 - CORE MISCELLANEOUS WIRE HARNESS ASSEMBLY -
INSPECTION ......................................... 1 6 3
FIGURE 22: ENGINE 2 - CORE MISCELLANEOUS WIRE HARNESS ASSEMBLY - INSPECTION . 167
FIGURE 23: ENGINE - CORE MISCELLANEOUS WIRE HARNESS ASSEMBLY - REPLACEMENT . 171
FIGURE 24: ENGINE - 30 DEGREE BULKHEAD WIRE HARNESS ASSEMBLY - INSPECTION . . . 175
FIGURE 25: ENGINE - 30 DEGREE BULKHEAD WIRE HARNESS ASSEMBLY - REPLACEMENT . 178
APPENDIX A: COMPLIANCE LOGIC DIAGRAM FOR PARAGRAPH 1.E., COMPLIANCE: TABLE 1: WORK
PACKAGE 1 - ENGINE 1, ENGINE 2, AND ENGINE 3 PYLON THRUST REVERSER WIRE
HARNESSES DETAILED INSPECTION ........................... 1 8 0
APPENDIX B: COMPLIANCE LOGIC DIAGRAM FOR PARAGRAPH 1.E., COMPLIANCE: TABLE 2: WORK
PACKAGE 2 - THRUST REVERSER CONTROL SYSTEM WIRE HARNESSES DETAILED
INSPECTIONS AND WIRE INTEGRITY TESTS ...................... 1 8 2
APPENDIX C: REPORTING FORM ..................................... 2 0 1
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### Page 5

Commercial 
Airplanes
MD11
Service Bulletin
ALERT
SummaryNumber: MD11-78A017Original Issue: December 04, 2023
ATA System: 7800 7834 7151
SUBJECT: ENGINE EXHAUST - Thrust Reverser - Thrust Reverser Wire Harnesses Inspection
and Test
THIS DOCUMENT IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN
PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS DOCUMENT
TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS DOCUMENT TO THE
NEW OWNER.
CONCURRENT REQUIREMENTS
None.
BACKGROUND
Accomplishment of this service bulletin will make sure that any damage to the Thrust Reverser (T/R) Control
System wire harnesses, T/R wire harnesses, and engine core compartment electrical harness is found and
repaired. Damage to the wire harnesses can cause an uncommanded T/R deployment. If this service bulletin
is not done, an in-flight T/R deployment can cause a loss of control and affect Continued Safe Flight and Landing
(CSFL).
The Boeing Company has received a report of an MD-11 experiencing an uncommanded T/R deployment of
the two transcowls on Engine 1 during takeoff at approximately 500 feet above ground level. In the Engine 1
pylon, damaged wiring was found, which could have caused or contributed to the deployment of the two
transcowls.
This service bulletin gives the instructions to inspect, test, and repair the T/R Control System wire harnesses,
T/R wire harnesses, and engine core compartment electrical harness. The inspections in this service bulletin
will make sure any damage to the T/R Control System wire harnesses, T/R wire harnesses, and engine core
compartment electrical harness is found and repaired before an uncommanded deployment of the T/R occurs.
Boeing Service Related Problem (SRP) MD11-SRP-78-0117 is related to this service bulletin.
Boeing Fleet Team Digest (FTD) MD-11 FTD 78-23001 is related to this service bulletin.
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### Page 6

This table is provided to operators for planning purposes only. Refer to the applicable sections for more
information.
ReferenceAffectedPlanning Data
Paragraph 1.A.2., Spares AffectedYesSpares Affected
Paragraph 1.E., Compliance and Paragraph
1.F., Approval
YesAD Related
Paragraph 1.F., ApprovalNoAlternative Method of Compliance (AMOC)
Paragraph 1.H., Weight and Balance ChangesNoWeight and Balance Change
Paragraph 1.I., Electrical Load DataNoElectrical Load Changed
Paragraph 1.K., Publications AffectedYesPublications Affected
Paragraph 1.K., Publications AffectedNoAirplane Flight Operations Affected (Flight Crew
Operations Manual and/or FAA Approved Air-
plane Flight Manual)
Paragraph 2.C.1., Kits/PartsNoKits/Parts Required
Paragraph 2.C.2., Parts and Materials Supplied
by the Operator
YesOperator Supplied Parts/Material
Paragraph 2.F., Special Tooling Necessary to
do this Service Bulletin
NoSpecial Tooling Required
ACTION
Work Package 1
1. Do a Detailed Inspection of the pylon T/R Control System wire harnesses for damage. Repair or replace
any damaged wire found.
Work Package 2
1. Do a Detailed Inspection and wire integrity tests of the T/R Control System wire harnesses, Left Side
and Right Side T/R wire harnesses, Junction Box, 30 degree Bulkhead wire harnesses, and engine
core electrical harness for damage. Repair or replace any damaged wire found. Repeat the Detailed
Inspection and wire integrity tests of the T/R Control System wire harnesses, Left Side and Right Side
T/R wire harnesses, Junction Box, 30 degree Bulkhead wire harnesses, and engine core electrical
harness for damage.
EFFECTIVITY
MD-11 and MD-11F Airplanes equipped with General Electric Engines. Refer to Paragraph 1.A.1., Airplanes for
the list of affected airplanes.
COMPLIANCE
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to this service
bulletin. The Airworthiness Directive will make the compliance tasks and times given in this service bulletin
mandatory.
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### Page 7

Refer to Paragraph 1.E., Compliance.
INDUSTRY SUPPORT INFORMATION
Boeing warranty remedies are not available for the configuration changes given in this service bulletin.
MANPOWER
Refer to Paragraph 1.G., Manpower.
MATERIAL INFORMATION
Boeing Supplied Kits/Parts.
Refer to Paragraph 2.A., Material - Price and Availability.
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### Page 8 (OCR)

BOEING SERVICE BULLETIN MD11-78A017
ALERT  ALERT
WORK PACKAGE 1
SYSTEM WIRE HARNESSES FOR DAMAGE REPAIR OR REPLACE
ANY DAMAGED WIRE FOUND.
WORK PACKAGE 2:
DO A DETAILED INSPECTION AND WIRE INTEGRITY TESTS OF
THE T/R CONTROL SYSTEM WIRE HARNESSES, LEFT SIDE AND
RIGHT SIDE T/R WIRE HARNESSES, JUNCTION BOX, 30 DEGREE
BULKHEAD WIRE HARNESSES, AND ENGINE CORE ELECTRICAL
HARNESS FOR DAMAGE. REPAIR OR REPLACE ANY DAMAGED
WIRE FOUND. REPEAT THE DETAILED INSPECTION AND WIRE
INTEGRITY TESTS OF THE T/R CONTROL SYSTEM WIRE
HARNESSES, LEFT SIDE AND RIGHT SIDE T/R WIRE HARNESSES,
JUNCTION BOX, 30 DEGREE BULKHEAD WIRE HARNESSES, AND  3047344
ENGINE CORE ELECTRICAL HARNESS FOR DAMAGE.
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MD11-78A017
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### Page 9

Commercial 
Airplanes
MD11
Service Bulletin
ALERT
Number: MD11-78A017
Original Issue: December 04, 2023
ATA System: 7800 7834 7151
SUBJECT: ENGINE EXHAUST - Thrust Reverser - Thrust Reverser Wire Harnesses Inspection
and Test
THIS DOCUMENT IS SENT TO THE OPERATORS OF RECORD OF THE AIRPLANES SHOWN IN
PARAGRAPH 1.A., EFFECTIVITY. IF AN AIRPLANE HAS BEEN LEASED OR SOLD, SEND THIS DOCUMENT
TO THE NEW OPERATOR. IF APPLICABLE SPARES HAVE BEEN SOLD, SEND THIS DOCUMENT TO THE
NEW OWNER.
1.    PLANNING INFORMATION
A. Effectivity
1. Airplanes
This bulletin is applicable to MD-11F Airplane(s), line number(s) 447-448, 451-454, 466-471, 474,
476, 478, 482-483, 486, 488, 491-493, 497, 499-505, 507-508, 513, 515, 517, 520-521, 523-524,
526-531, 534-535, 537, 540, 545, 547-551, 554-555, 564-565, 567, 570, 572, 576, 580, 587, 589,
592, 594-596, 598, 600-604, 607-609, 613, 615-620, 624-631, 633-634, 637, 639-646 in 1 Group(s).
Where the effectivity is presented with hyphens between line numbers, the airplane applicability
means "through" and "inclusive", e.g. line numbers 1-9 means line numbers 1 through 9 inclusive.
Refer to Service Bulletin Index D624N001 Part 3 for Airplane Variable Number, Line Number, and
Serial Number data
The Fuselage Numbers and Group Information for the applicable airplanes is given below.
DESCRIPTIONCONFIGURATIONGROUP
MD-11, MD-11F Airplanes equipped with General Electric (GE)
Engines.
-1
Airplane Models:
MD-11F
GroupFuselage Number
1447 - 448
1451 - 454
GroupFuselage Number
1466 - 471
1474
GroupFuselage Number
1476
1478
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### Page 10

GroupFuselage Number
1482 - 483
1486
1488
1491 - 493
1497
1499 - 505
1507 - 508
1513
1515
1517
1520 - 521
1523 - 524
1526 - 531
GroupFuselage Number
1534 - 535
1537
1540
1545
1547 - 551
1554 - 555
1564 - 565
1567
1570
1572
1576
1580
1587
GroupFuselage Number
1589
1592
1594 - 596
1598
1600 - 604
1607 - 609
1613
1615 - 620
1624 - 631
1633 - 634
1637
1639 - 646
--
2. Spares Affected
Examine your spares supply for the parts or components identified below. If any parts or components
are found, refer to Paragraph 3.B., Work Instructions for the recommended action.
Part Number
AUN7613-( )
B. Concurrent Requirements
None.
C. Reason
Accomplishment of this service bulletin will make sure that any damage to the Thrust Reverser (T/R)
Control System wire harnesses, T/R wire harnesses, and engine core compartment electrical harness
is found and repaired. Damage to the wire harnesses can cause an uncommanded T/R deployment.
If this service bulletin is not done an in-flight T/R deployment can cause a loss of control and affect
Continued Safe Flight and Landing (CSFL).
The Boeing Company has received a report of an MD-11 experiencing an uncommanded T/R deployment
of the two transcowls on Engine 1 during takeoff at approximately 500 feet above ground level. In the
Engine 1 pylon, damaged wiring was found, which could have caused or contributed to the deployment
of the two transcowls.
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### Page 11

This service bulletin gives the instructions to inspect, test, and repair the T/R Control System wire
harnesses, T/R wire harnesses, and engine core compartment electrical harness. The inspections in
this service bulletin will make sure any damage to the T/R Control System wire harnesses, T/R wire
harnesses, and engine core compartment electrical harness is found and repaired before an
uncommanded deployment of the T/R occurs.
Boeing Service Related Problem (SRP) MD11-SRP-78-0117 is related to this service bulletin.
Boeing Fleet Team Digest (FTD) MD-11 FTD 78-23001 is related to this service bulletin.
D. Description
Work Package 1
1. Do a Detailed Inspection of the pylon T/R Control System wire harnesses for damage. Repair or
replace any damaged wire found.
Work Package 2
1. Do a Detailed Inspection and wire integrity tests of the T/R Control System wire harnesses, Left
Side and Right Side T/R wire harnesses, Junction Box, 30 degree Bulkhead wire harnesses, and
engine core electrical harness for damage. Repair or replace any damaged wire found. Repeat
the Detailed Inspection and wire integrity tests of the T/R Control System wire harnesses, Left
Side and Right Side T/R wire harnesses, Junction Box, 30 degree Bulkhead wire harnesses, and
engine core electrical harness for damage.
The work in this service bulletin is done in the maintenance zone(s) given below.
Affected Maintenance Zones
ZoneModel
112, 123, 127, 131, 132, 231, 232, 251, 252,
261, 262, 363, 364, 415, 433, 434, 437, 438,
443, 453, 454, 457, 465, 483, 484, 487, 488,
515, 516, 517, 615, 616, 617
MD-11F
E. Compliance
The Federal Aviation Administration (FAA) will possibly release an Airworthiness Directive related to
this service bulletin. The Airworthiness Directive will make the compliance tasks and times given in this
service bulletin mandatory.
Accomplish the required action(s), based on the applicable condition(s) in Tables 1 and 2, in accordance
with Paragraph 3. Accomplishment Instructions.
When more than one OPTION is given for a CONDITION, do only one of the OPTION numbers. When
more than one ACTION is given for a CONDITION or an OPTION, do all of the ACTION numbers for
that CONDITION or OPTION.
Logic diagrams showing compliance tasks and compliance times are included as an aid in APPENDIX
A and APPENDIX B.
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### Page 12

Table 1: Work Package 1 - Engine 1, Engine 2, and Engine 3 Pylon Thrust Reverser Control System Wire
Harnesses Detailed Inspection
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
-Within 12 months
after the original
issue date of this
service bulletin.
Do PART 2: ENGINE 1, ENGINE 2,
AND ENGINE 3 PYLON WIRE
HARNESS DETAILED INSPEC-
TION for wire chafing damage, signs
of arcing, and riding conditions. (a)
All Airplanes.
-Before further
flight.
CONDITION 1 (ACTION 1): Do
PART 4: WORK PACKAGE 1 RE-
TURN TO SERVICE TESTS AND
CLOSE ACCESS.
CONDITION 1: NO WIRE CHAF-
ING DAMAGE FOUND, NO
SIGNS OF ARCING, AND NO
RIDING CONDITIONS FOUND
during PART 2: ENGINE 1, EN-
GINE 2, AND ENGINE 3 PYLON
WIRE HARNESS DETAILED IN-
SPECTION.
-At the times speci-
fied in Table 2.
CONDITION 1 (ACTION 2): Do the
actions specified in Work Package
2.
-Before further
flight.
CONDITION 2 (ACTION 1): Do
PART 3: WIRE HARNESS REPAIR.
CONDITION 2: ANY WIRE
CHAFING DAMAGE FOUND,
ANY SIGNS OF ARCING, OR
ANY RIDING CONDITIONS
FOUND during PART 2: ENGINE
1, ENGINE 2, AND ENGINE 3
PYLON WIRE HARNESS DE-
TAILED INSPECTION.
-Before further
flight.
CONDITION 2 (ACTION 2): Do
PART 4: WORK PACKAGE 1 RE-
TURN TO SERVICE TESTS AND
CLOSE ACCESS.
-At the times speci-
fied in Table 2.
CONDITION 2 (ACTION 3): Do the
actions specified in Work Package
2.
(a) Accomplishing the initial ACTION 1 through 3 inclusive specified in Work Package 2 terminates the Work
Package 1 PART 2: ENGINE 1, ENGINE 2, AND ENGINE 3 PYLON WIRE HARNESS DETAILED IN-
SPECTION requirement.
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### Page 13

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
-Within 27 months
after the original
issue date of this
service bulletin.
ACTION 1: Do PART 6: ENGINE 1
THRUST REVERSER CONTROL
SYSTEM WIRE HARNESSES DE-
TAILED INSPECTION AND WIRE
INTEGRITY TESTS for wire chafing
damage, riding conditions, signs of
arcing, and wire integrity tests fail-
ure. (a)(b)
All Airplanes.
ACTION 2: Do PART 7: ENGINE 2
THRUST REVERSER CONTROL
SYSTEM WIRE HARNESSES DE-
TAILED INSPECTION AND WIRE
INTEGRITY TESTS for wire chafing
damage, riding conditions, signs of
arcing, and wire integrity tests fail-
ure. (a)(b)
ACTION 3: Do PART 8: ENGINE 3
THRUST REVERSER CONTROL
SYSTEM WIRE HARNESSES DE-
TAILED INSPECTION AND WIRE
INTEGRITY TESTS for wire chafing
damage, riding conditions, signs of
arcing, and wire integrity tests fail-
ure. (a)(b)
On each of the Engine 1, Engine 2,
and Engine 3 junction box, do as
follows: ACTION 4: Do PART 10:
JUNCTION BOX DETAILED IN-
SPECTION for wire chafing damage
and signs of arcing.
On each of the Engine 1, Engine 2,
and Engine 3 junction box, do as
follows: ACTION 5: Do PART 13:
JUNCTION BOX COVER DE-
TAILED INSPECTION for burn
marks, signs of arcing, and fretting
to the internal surface of the Junc-
tion Box Cover.
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### Page 14

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
On each of the Engine 1, Engine 2,
and Engine 3 junction box, do as
follows: ACTION 6: Do PART 16:
JUNCTION BOX WIRE INTEGRITY
TESTS to test for wire integrity tests
failure. (b)
On each Engine (Engine 1, Engine
2, and Engine 3), do as follows:
ACTION 7: Do PART 19: LEFT
SIDE AND RIGHT SIDE THRUST
REVERSER ELECTRICAL HAR-
NESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS for
wire chafing damage, signs of arc-
ing, and wire integrity tests failure.
(c)
On each Engine (Engine 1, Engine
2, and Engine 3), do as follows:
ACTION 8: Do PART 24: CORE
MISCELLANEOUS WIRE HAR-
NESS ASSEMBLY DETAILED IN-
SPECTION AND WIRE INTEGRITY
TESTS for wire chafing damage,
signs of arcing, and wire integrity
tests failure. (b)
On each Engine (Engine 1, Engine
2, and Engine 3), do as follows:
ACTION 9: Do PART 27: 30 DE-
GREE BULKHEAD WIRE HAR-
NESS ASSEMBLY DETAILED IN-
SPECTION AND WIRE INTEGRITY
TESTS for wire chafing damage,
signs of arcing, and wire integrity
tests failure. (b)
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### Page 15

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
24 months.-Repeat PART 6: ENGINE 1
THRUST REVERSER CONTROL
SYSTEM WIRE HARNESSES DE-
TAILED INSPECTION AND WIRE
INTEGRITY TESTS for wire chafing
damage, riding conditions, signs of
arcing, and wire integrity tests fail-
ure. (b)
CONDITION 3: NO WIRE CHAF-
ING DAMAGE FOUND, NO RID-
ING CONDITIONS FOUND, NO
SIGNS OF ARCING FOUND,
AND WIRE INTEGRITY TESTS
PASSED during PART 6: ENGINE
1 THRUST REVERSER CON-
TROL SYSTEM WIRE HARNESS-
ES DETAILED INSPECTION AND
WIRE INTEGRITY TESTS. (b)
-Before further
flight.
CONDITION 4 (ACTION 1): Do
PART 3: WIRE HARNESS REPAIR.
CONDITION 4: ANY WIRE
CHAFING DAMAGE FOUND,
ANY RIDING CONDITIONS
FOUND, ANY SIGNS OF ARC-
ING FOUND, OR ANY WIRE IN-
TEGRITY TEST FAILED during
PART 6: ENGINE 1 THRUST
REVERSER CONTROL SYSTEM
WIRE HARNESSES DETAILED
INSPECTION AND WIRE IN-
TEGRITY TESTS. (b)
24 months.-CONDITION 4 (ACTION 2): Repeat
PART 6: ENGINE 1 THRUST RE-
VERSER CONTROL SYSTEM
WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRI-
TY TESTS for wire chafing damage,
riding conditions, signs of arcing,
and wire integrity tests failure. (b)
24 months.-Repeat PART 7: ENGINE 2
THRUST REVERSER CONTROL
SYSTEM WIRE HARNESSES IN-
SPECTION AND WIRE INTEGRITY
TESTS for wire chafing damage,
riding conditions, signs of arcing,
and wire integrity tests failure. (b)
CONDITION 5: NO WIRE CHAF-
ING DAMAGE FOUND, NO RID-
ING CONDITIONS FOUND, NO
SIGNS OF ARCING FOUND,
AND WIRE INTEGRITY TESTS
PASSED during PART 7: ENGINE
2 THRUST REVERSER CON-
TROL SYSTEM WIRE HARNESS-
ES INSPECTION AND WIRE IN-
TEGRITY TESTS. (b)
-Before further
flight.
CONDITION 6 (ACTION 1): Do
PART 3: WIRE HARNESS REPAIR.
CONDITION 6: ANY WIRE
CHAFING DAMAGE FOUND,
ANY RIDING CONDITIONS
FOUND, ANY SIGNS OF ARC-
ING FOUND, OR ANY WIRE IN-
TEGRITY TEST FAILED during
PART 7: ENGINE 2 THRUST
REVERSER CONTROL SYSTEM
WIRE HARNESSES DETAILED
INSPECTION AND WIRE IN-
TEGRITY TESTS. (b)
24 months.-CONDITION 6 (ACTION 2): Repeat
PART 7: ENGINE 2 THRUST RE-
VERSER CONTROL SYSTEM
WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRI-
TY TESTS for wire chafing damage,
riding conditions, signs of arcing,
and wire integrity tests failure. (b)
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
15 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

### Page 16

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
24 months.-Repeat PART 8: ENGINE 3
THRUST REVERSER CONTROL
SYSTEM WIRE HARNESSES DE-
TAILED INSPECTION AND WIRE
INTEGRITY TESTS for wire chafing
damage, riding conditions, signs of
arcing, and wire integrity tests fail-
ure. (b)
CONDITION 7: NO WIRE CHAF-
ING DAMAGE FOUND, NO RID-
ING CONDITIONS FOUND, NO
SIGNS OF ARCING FOUND,
AND WIRE INTEGRITY TESTS
PASSED during PART 8: ENGINE
3 THRUST REVERSER CON-
TROL SYSTEM WIRE HARNESS-
ES DETAILED INSPECTION AND
WIRE INTEGRITY TESTS. (b)
-Before further
flight.
CONDITION 8 (ACTION 1): Do
PART 3: WIRE HARNESS REPAIR.
CONDITION 8: ANY WIRE
CHAFING DAMAGE FOUND,
ANY RIDING CONDITIONS
FOUND, ANY SIGNS OF ARC-
ING FOUND, OR ANY WIRE IN-
TEGRITY TEST FAILED during
PART 8: ENGINE 3 THRUST
REVERSER CONTROL SYSTEM
WIRE HARNESSES DETAILED
INSPECTION AND WIRE IN-
TEGRITY TESTS. (b)
24 months.-CONDITION 8 (ACTION 2): Repeat
PART 8: ENGINE 3 THRUST RE-
VERSER CONTROL SYSTEM
WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRI-
TY TESTS for wire chafing damage,
riding conditions, signs of arcing,
continuity test failure, and wire in-
tegrity tests failure. (b)
24 months.-Repeat PART 10: JUNCTION BOX
DETAILED INSPECTION for wire
chafing damage and signs of arcing.
CONDITION 9: NO WIRE CHAF-
ING DAMAGE FOUND AND NO
SIGNS OF ARCING FOUND dur-
ing PART 10: JUNCTION BOX
DETAILED INSPECTION.
-Before further
flight.
CONDITION 10 OPTION 1 (AC-
TION 1): Do PART 11: JUNCTION
BOX REPAIR.
CONDITION 10: ANY WIRE
CHAFING DAMAGE FOUND OR
ANY SIGNS OF ARCING FOUND
during PART 10: JUNCTION BOX
DETAILED INSPECTION. 24 months.-CONDITION 10 OPTION 1 (AC-TION 2): Repeat PART 10: JUNC-
TION BOX DETAILED INSPEC-
TION for wire chafing damage and
signs of arcing.
-Before further
flight.
CONDITION 10 OPTION 2 (AC-
TION 1): Do PART 12: JUNCTION
BOX REPLACEMENT.
24 months.-CONDITION 10 OPTION 2 (AC-
TION 2): Repeat PART 10: JUNC-
TION BOX DETAILED INSPEC-
TION for wire chafing damage and
signs of arcing.
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
16 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

### Page 17

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
24 months.-Repeat PART 10: JUNCTION BOX
DETAILED INSPECTION for wire
chafing damage and signs of arcing.
CONDITION 10.1: NO WIRE
CHAFING DAMAGE FOUND, NO
SIGNS OF ARCING FOUND,
CONTINUITY TEST PASSED
AND INSULATION RESISTANCE
TEST PASSED during PART 12:
JUNCTION BOX REPLACE-
MENT.
-Before further
flight.
CONDITION 10.2 OPTION 1: Do
PART 12: JUNCTION BOX RE-
PLACEMENT.
CONDITION 10.2: ANY WIRE
CHAFING DAMAGE FOUND,
ANY SIGNS OF ARCING
FOUND, ANY CONTINUITY
TEST FAILED, OR ANY INSULA-
TION RESISTANCE TEST
FAILED during PART 12: JUNC-
TION BOX REPLACEMENT.
-Before further
flight.
CONDITION 10.2 OPTION 2 (AC-
TION 1): Do PART 11: JUNCTION
BOX REPAIR.
24 months.-CONDITION 10.2 OPTION 2 (AC-
TION 2): Repeat PART 10: JUNC-
TION BOX DETAILED INSPEC-
TION for wire chafing damage and
signs of arcing.
-Before further
flight.
CONDITION 11 (ACTION 1): Do
PART 14: JUNCTION BOX COVER
INSTALLATION.
CONDITION 11: NO BURN
MARKS FOUND, NO SIGNS OF
ARCING FOUND, AND NO
FRETTING FOUND ON THE IN-
TERNAL SURFACE OF THE
JUNCTION BOX COVER during
PART 13: JUNCTION BOX COV-
ER DETAILED INSPECTION.
24 months.-CONDITION 11 (ACTION 2): Re-
peat PART 13: JUNCTION BOX
COVER DETAILED INSPECTION
for burn marks, signs of arcing, and
fretting to the internal surface of the
Junction Box Cover.
-Before further
flight.
CONDITION 12 (ACTION 1): Do
PART 15: JUNCTION BOX COVER
REPLACEMENT.
CONDITION 12: ANY BURN
MARK FOUND, ANY SIGNS OF
ARCING FOUND, OR FRETTING
FOUND ON THE INTERNAL
SURFACE OF THE JUNCTION
BOX COVER during PART 13:
JUNCTION BOX COVER INSPEC-
TION.
24 months.-CONDITION 12 (ACTION 2): Re-
peat PART 13: JUNCTION BOX
COVER DETAILED INSPECTION
for burn marks, signs of arcing, and
fretting to the internal surface of the
Junction Box Cover.
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
17 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

### Page 18

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
-Before further
flight.
CONDITION 13 (ACTION 1): Do
PART 18: ENGINE 1, ENGINE 2,
AND ENGINE 3 PYLON JUNCTION
BOX INSTALLATION.
CONDITION 13: WIRE INTEGRI-
TY TESTS PASSED during PART
16: JUNCTION BOX WIRE IN-
TEGRITY TESTS. (b)
24 months.-CONDITION 13 (ACTION 2): Re-
peat PART 16: JUNCTION BOX
WIRE INTEGRITY TESTS. (b)
-Before further
flight.
CONDITION 14 OPTION 1 (AC-
TION 1): Replace the Junction Box.
CONDITION 14: ANY WIRE IN-
TEGRITY TEST FAILED during
PART 16: JUNCTION BOX WIRE
INTEGRITY TESTS. (b) -Before furtherflight.CONDITION 14 OPTION 1 (AC-TION 2): Do PART 17: POST
JUNCTION BOX REPLACEMENT
DETAILED INSPECTION AND
WIRE INTEGRITY TESTS for burn
marks, signs of arcing, and fretting
to the internal surface of the Junc-
tion Box cover, wire chafing dam-
age, signs of arcing, and wire integri-
ty tests failure in the Junction Box.
(b)
-Before further
flight.
CONDITION 14 OPTION 2 (AC-
TION 1): Do PART 11: JUNCTION
BOX REPAIR.
-Before further
flight.
CONDITION 14 OPTION 2 (AC-
TION 2): Do PART 14: JUNCTION
BOX COVER INSTALLATION.
-Before further
flight.
CONDITION 14 OPTION 2 (AC-
TION 3): Repeat PART 16: JUNC-
TION BOX WIRE INTEGRITY
TESTS to test for wire integrity tests
failure. (b)
Export Controlled ECCN: 9E991
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Original Issue: December 04, 2023
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### Page 19

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
-Before further
flight.
CONDITION 14.1 (ACTION 1): Do
PART 14: JUNCTION BOX COVER
INSTALLATION.
CONDITION 14.1: NO BURN
MARKS, NO SIGNS OF ARCING
FOUND, AND NO FRETTING
FOUND ON THE INTERNAL
SURFACE OF THE JUNCTION
BOX COVER, AND NO WIRE
CHAFING DAMAGE FOUND, NO
SIGNS OF ARCING FOUND,
AND WIRE INTEGRITY TESTS
PASSED IN THE JUNCTION BOX
during PART 17: POST JUNC-
TION BOX REPLACEMENT DE-
TAILED INSPECTION AND WIRE
INTEGRITY TESTS. (b)
-Before further
flight.
CONDITION 14.1 (ACTION 2): Re-
peat PART 16: JUNCTION BOX
WIRE INTEGRITY TESTS to test
for wire integrity tests failure. (b)
-Before further
flight.
CONDITION 14.2 (ACTION 1): Do
PART 11: JUNCTION BOX RE-
PAIR.
CONDITION 14.2: ANY BURN
MARKS, ANY SIGNS OF ARC-
ING FOUND,AND ANY FRET-
TING FOUND ON THE INTER-
NAL SURFACE OF THE JUNC-
TION BOX COVER, AND ANY
WIRE CHAFING DAMAGE
FOUND AND ANY SIGNS OF
ARCING FOUND IN THE JUNC-
TION BOX during PART 17:POST
JUNCTION BOX REPLACEMENT
DETAILED INSPECTION AND
WIRE INTEGRITY TESTS. (b)
-Before further
flight.
CONDITION 14.2 (ACTION 2): Do
PART 15: JUNCTION BOX COVER
REPLACEMENT.
-Before further
flight.
CONDITION 14.2 (ACTION 3): Re-
peat PART 16: JUNCTION BOX
WIRE INTEGRITY TESTS to test
for wire integrity tests failure. (b)
-Before further
flight.
CONDITION 14.3 (ACTION 1): Do
PART 15: JUNCTION BOX COVER
REPLACEMENT.
CONDITION 14.3: ANY BURN
MARKS, ANY SIGNS OF ARC-
ING FOUND, AND ANY FRET-
TING FOUND ON THE INTER-
NAL SURFACE OF THE JUNC-
TION BOX COVER, AND NO
WIRE CHAFING DAMAGE
FOUND, NO SIGNS OF ARCING
FOUND, AND WIRE INTEGRITY
TESTS PASSED IN THE JUNC-
TION BOX during PART 17:
POST JUNCTION BOX RE-
PLACEMENT DETAILED INSPEC-
TION AND WIRE INTEGRITY
TESTS. (b)
-Before further
flight.
CONDITION 14.3 (ACTION 2): Re-
peat PART 16: JUNCTION BOX
WIRE INTEGRITY TESTS to test
for wire integrity tests failure. (b)
Export Controlled ECCN: 9E991
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Original Issue: December 04, 2023
MD11-78A017
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### Page 20

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
-Before further
flight.
CONDITION 14.4 OPTION 1 (AC-
TION 1): Do PART 11: JUNCTION
BOX REPAIR.
CONDITION 14.4: NO BURN
MARKS, NO SIGNS OF ARCING
FOUND, AND NO FRETTING
FOUND ON THE INTERNAL
SURFACE OF THE JUNCTION
BOX COVER, AND ANY WIRE
CHAFING DAMAGE FOUND OR
ANY SIGNS OF ARCING FOUND
IN THE JUNCTION BOX during
PART 17: POST JUNCTION BOX
REPLACEMENT DETAILED IN-
SPECTION AND WIRE INTEGRI-
TY TESTS. (b)
-Before further
flight.
CONDITION 14.4 OPTION 1 (AC-
TION 2): Do PART 14: JUNCTION
BOX COVER INSTALLATION.
-Before further
flight.
CONDITION 14.4 OPTION 1 (AC-
TION 3): Repeat PART 16: JUNC-
TION BOX WIRE INTEGRITY
TESTS to test for wire integrity tests
failure. (b)
-Before further
flight.
CONDITION 14.4 OPTION 2 (AC-
TION 1): Replace the Junction Box.
-Before further
flight.
CONDITION 14.4 OPTION 2 (AC-
TION 2): Do PART 17: POST
JUNCTION BOX REPLACEMENT
DETAILED INSPECTION AND
WIRE INTEGRITY TESTS for burn
marks, signs of arcing, and fretting
to the internal surface of the Junc-
tion Box cover, wire chafing dam-
age, signs of arcing, and wire integri-
ty tests failure in the Junction Box.
(b)
24 months.-Repeat PART 19: LEFT SIDE AND
RIGHT SIDE THRUST REVERSER
ELECTRICAL HARNESS DE-
TAILED INSPECTION AND WIRE
INTEGRITY TESTS for wire chafing
damage, signs of arcing, and wire
integrity tests failure. (c)
CONDITION 15: NO WIRE
CHAFING DAMAGE FOUND, NO
SIGNS OF ARCING FOUND,
AND WIRE INTEGRITY TESTS
PASSED, ON BOTH THE LEFT
SIDE AND RIGHT SIDE THRUST
REVERSER ELECTRICAL HAR-
NESS, during PART 19: LEFT
SIDE AND RIGHT SIDE THRUST
REVERSER ELECTRICAL HAR-
NESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS.
(c)
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
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ALERTALERT

### Page 21

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
-Before further
flight.
CONDITION 16 OPTION 1 (AC-
TION 1): Do PART 20: RIGHT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPLACEMENT.
CONDITION 16: ANY WIRE
CHAFING DAMAGE FOUND,
ANY SIGNS OF ARCING
FOUND, OR WIRE INTEGRITY
TESTS FAILED ON THE RIGHT
SIDE THRUST REVERSER
ELECTRICAL HARNESS during
PART 19: LEFT SIDE AND
RIGHT SIDE THRUST REVERS-
ER ELECTRICAL HARNESS DE-
TAILED INSPECTION AND WIRE
INTEGRITY TESTS BUT NO
WIRE CHAFING DAMAGE
FOUND, NO SIGNS OF ARCING
FOUND, AND WIRE INTEGRITY
TESTS PASSED ON THE LEFT
SIDE THRUST REVERSER
ELECTRICAL HARNESS. (c)
24 months.-CONDITION 16 OPTION 1 (AC-
TION 2): Repeat PART 19: LEFT
SIDE AND RIGHT SIDE THRUST
REVERSER ELECTRICAL HAR-
NESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS for
wire chafing damage, signs of arc-
ing, and wire integrity tests failure.
(c)
-Before further
flight.
CONDITION 16 OPTION 2 (AC-
TION 1): Do PART 22: RIGHT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPAIR.
24 months.-CONDITION 16 OPTION 2 (AC-
TION 2): Repeat PART 19: LEFT
SIDE AND RIGHT SIDE THRUST
REVERSER ELECTRICAL HAR-
NESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS for
wire chafing damage, signs of arc-
ing, and wire integrity tests failure.
(c)
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
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### Page 22

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
-Before further
flight.
CONDITION 17 OPTION 1 (AC-
TION 1): Do PART 21: LEFT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPLACEMENT.
CONDITION 17: ANY WIRE
CHAFING DAMAGE FOUND,
ANY SIGNS OF ARCING
FOUND, OR WIRE INTEGRITY
TESTS FAILED ON THE LEFT
SIDE THRUST REVERSER
ELECTRICAL HARNESS during
PART 19: LEFT SIDE AND
RIGHT SIDE THRUST REVERS-
ER ELECTRICAL HARNESS DE-
TAILED INSPECTION AND WIRE
INTEGRITY TESTS BUT NO
WIRE CHAFING DAMAGE
FOUND, NO SIGNS OF ARCING
FOUND, AND WIRE INTEGRITY
TESTS PASSED ON THE RIGHT
SIDE THRUST REVERSER
ELECTRICAL HARNESS. (c)
24 months.-CONDITION 17 OPTION 1 (AC-
TION 2): Repeat PART 19:
THRUST REVERSER ELECTRI-
CAL HARNESS INSPECTION AND
WIRE INTEGRITY TESTS for wire
chafing damage, signs of arcing,
and wire integrity tests failure. (c)
-Before further
flight.
CONDITION 17 OPTION 2 (AC-
TION 1): Do PART 23: LEFT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPAIR.
24 months.-CONDITION 17 OPTION 2 (AC-
TION 2): Repeat PART 19: LEFT
SIDE AND RIGHT SIDE THRUST
REVERSER ELECTRICAL HAR-
NESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS for
wire chafing damage, signs of arc-
ing, and wire integrity tests failure.
(c)
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
22 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

### Page 23

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
-Before further
flight.
CONDITION 18 OPTION 1 (AC-
TION 1): Do PART 21: LEFT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPLACEMENT.
CONDITION 18: ANY WIRE
CHAFING DAMAGE FOUND,
ANY SIGNS OF ARCING
FOUND, OR WIRE INTEGRITY
TESTS FAILED ON BOTH THE
LEFT SIDE AND RIGHT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESSES during PART
19: LEFT SIDE AND RIGHT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS DETAILED IN-
SPECTION AND WIRE INTEGRI-
TY TESTS. (c)
-Before further
flight.
CONDITION 18 OPTION 1 (AC-
TION 2): Do PART 20: RIGHT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPLACEMENT.
24 months.-CONDITION 18 OPTION 1 (AC-
TION 3): Repeat PART 19: LEFT
SIDE AND RIGHT SIDE THRUST
REVERSER ELECTRICAL HAR-
NESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS for
wire chafing damage, signs of arc-
ing, and wire integrity tests failure.
(c)
-Before further
flight.
CONDITION 18 OPTION 2 (AC-
TION 1): Do PART 23: LEFT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPAIR.
-Before further
flight.
CONDITION 18 OPTION 2 (AC-
TION 2): Do PART 22: RIGHT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPAIR.
24 months.-CONDITION 18 OPTION 2 (AC-
TION 3): Repeat PART 19: LEFT
SIDE AND RIGHT SIDE THRUST
REVERSER ELECTRICAL HAR-
NESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS for
wire chafing damage, signs of arc-
ing, and wire integrity tests failure.
(c)
-Before further
flight.
CONDITION 18 OPTION 3 (AC-
TION 1): Do PART 23: LEFT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPAIR.
-Before further
flight.
CONDITION 18 OPTION 3 (AC-
TION 2): Do PART 20: RIGHT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPLACEMENT.
Export Controlled ECCN: 9E991
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Original Issue: December 04, 2023
MD11-78A017
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ALERTALERT

### Page 24

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
CONDITION 18 OPTION 3 (AC-
TION 3): Repeat PART 19: LEFT
SIDE AND RIGHT SIDE THRUST
REVERSER ELECTRICAL HAR-
NESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS for
wire chafing damage, signs of arc-
ing, and wire integrity tests failure.
(c)
24 months.-
-Before further
flight.
CONDITION 18 OPTION 4 (AC-
TION 1): Do PART 21: LEFT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPLACEMENT.
-Before further
flight.
CONDITION 18 OPTION 4 (AC-
TION 2): Do PART 22: RIGHT SIDE
THRUST REVERSER ELECTRI-
CAL HARNESS REPAIR.
24 months.-CONDITION 18 OPTION 4 (AC-
TION 3): Repeat PART 19: LEFT
SIDE AND RIGHT SIDE THRUST
REVERSER ELECTRICAL HAR-
NESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS for
wire chafing damage, signs of arc-
ing, and wire integrity tests failure.
(c)
24 months.-Repeat PART 24: CORE MISCEL-
LANEOUS WIRE HARNESS AS-
SEMBLY DETAILED INSPECTION
AND WIRE INTEGRITY TESTS for
wire chafing damage, signs of arc-
ing, and wire integrity tests failure.
(b)
CONDITION 19: NO WIRE
CHAFING DAMAGE FOUND, NO
SIGNS OF ARCING FOUND,
AND WIRE INTEGRITY TESTS
PASSED during PART 24: CORE
MISCELLANEOUS WIRE HAR-
NESS ASSEMBLY DETAILED
INSPECTION AND WIRE IN-
TEGRITY TESTS. (b)
Export Controlled ECCN: 9E991
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Original Issue: December 04, 2023
MD11-78A017
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### Page 25

Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
-Before further
flight.
CONDITION 20 OPTION 1 (AC-
TION 1): Do PART 25: CORE MIS-
CELLANEOUS WIRE HARNESS
ASSEMBLY REPLACEMENT.
CONDITION 20: ANY WIRE
CHAFING DAMAGE FOUND,
ANY SIGNS OF ARCING
FOUND, OR ANY WIRE INTEGRI-
TY TEST FAILED during PART
24: CORE MISCELLANEOUS
WIRE HARNESS ASSEMBLY
DETAILED INSPECTION AND
WIRE INTEGRITY TESTS. (b)
24 months.-CONDITION 20 OPTION 1 (AC-
TION 2): Repeat PART 24: CORE
MISCELLANEOUS WIRE HAR-
NESS ASSEMBLY DETAILED IN-
SPECTION AND WIRE INTEGRITY
TESTS for wire chafing damage,
signs of arcing, and wire integrity
tests failure. (b)
-Before further
flight.
CONDITION 20 OPTION 2 (AC-
TION 1): Do PART 26: CORE MIS-
CELLANEOUS WIRE HARNESS
ASSEMBLY REPAIR.
24 months.-CONDITION 20 OPTION 2 (AC-
TION 2): Repeat PART 24: CORE
MISCELLANEOUS WIRE HAR-
NESS ASSEMBLY DETAILED IN-
SPECTION AND WIRE INTEGRITY
TESTS for wire chafing damage,
signs of arcing, and wire integrity
tests failure. (b)
-Before further
flight.
CONDITION 21 (ACTION 1): Do
PART 30: WORK PACKAGE 2 RE-
TURN TO SERVICE TESTS AND
CLOSE ACCESS.
CONDITION 21: NO WIRE
CHAFING DAMAGE FOUND, NO
SIGNS OF ARCING FOUND,
AND WIRE INTEGRITY TESTS
PASSED during PART 27: 30
DEGREE BULKHEAD WIRE
HARNESS ASSEMBLY DE-
TAILED INSPECTION AND WIRE
INTEGRITY TESTS. (b)
24 months.-CONDITION 21 (ACTION 2): Re-
peat PART 27: 30 DEGREE BULK-
HEAD WIRE HARNESS ASSEM-
BLY DETAILED INSPECTION AND
WIRE INTEGRITY TESTS. (b)
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Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
Repeat Interval
(Not to Exceed)
Boeing Recom-
mended
Compliance Time
ActionCondition
-Before further
flight.
CONDITION 22 OPTION 1 (AC-
TION 1): Do PART 28: 30 DEGREE
BULKHEAD WIRE HARNESS AS-
SEMBLY REPLACEMENT.
CONDITION 22: ANY WIRE
CHAFING DAMAGE FOUND,
ANY SIGNS OF ARCING
FOUND, OR ANY WIRE INTEGRI-
TY TEST FAILED during PART
27: 30 DEGREE BULKHEAD
WIRE HARNESS ASSEMBLY
DETAILED INSPECTION AND
WIRE INTEGRITY TESTS. (b)
-Before further
flight.
CONDITION 22 OPTION 1 (AC-
TION 2): Do PART 30: WORK
PACKAGE 2 RETURN TO SER-
VICE TESTS AND CLOSE AC-
CESS.
24 months.-CONDITION 22 OPTION 1 (AC-
TION 3): Repeat PART 27: 30 DE-
GREE BULKHEAD WIRE HAR-
NESS ASSEMBLY DETAILED IN-
SPECTION AND WIRE INTEGRITY
TESTS for wire chafing damage,
signs of arcing, and wire integrity
tests failure. (b)
-Before further
flight.
CONDITION 22 OPTION 2 (AC-
TION 1): Do PART 29: 30 DEGREE
BULKHEAD WIRE HARNESS AS-
SEMBLY REPAIR.
-Before further
flight.
CONDITION 22 OPTION 2 (AC-
TION 2): Do PART 30: WORK
PACKAGE 2 RETURN TO SER-
VICE TESTS AND CLOSE AC-
CESS.
24 months.-CONDITION 22 OPTION 2 (AC-
TION 3): Repeat PART 27: 30 DE-
GREE BULKHEAD WIRE HAR-
NESS ASSEMBLY DETAILED IN-
SPECTION AND WIRE INTEGRITY
TESTS for wire chafing damage,
signs of arcing, and wire integrity
tests failure. (b)
(a) Accomplishing ACTION 1 through 3 inclusive terminates the Work Package 1 PART 2 ENGINE 1, ENGINE
2, AND ENGINE 3 PYLON WIRE HARNESS DETAILED INSPECTION requirement.
(b) Wire integrity tests consist of a continuity test and an insulation resistance test.
(c) Wire integrity tests consist of a continuity test, a conductivity test, and an insulation resistance.
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F. Approval
This service bulletin was examined by the Federal Aviation Administration (FAA). The changes specified
in this service bulletin comply with the applicable regulations and are FAA approved. This service
bulletin and its approval were based on the airplane in its original Boeing delivery configuration or as
modified by other approved Boeing changes.
If an airplane has a non-Boeing modification or repair that affects a component or system also affected
by this service bulletin, the operator is responsible for obtaining appropriate regulatory agency approval
before incorporating this service bulletin.
G. Manpower
The tables below show an estimate of the task hours necessary to do this modification for each airplane.
This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with the operator
task hour data if necessary. The estimate does not include lost time. These are some examples of lost
time:
— Time to adjust to the workplace
— Time to schedule the work
— Time to examine the work
— Time to cure the materials
— Time to make the parts
— Time to find the tools.
Table 1: Work Package 1 - Engine 1, Engine 2, and Engine 3 Pylon Thrust Reverser Control
System Wire Harnesses Detailed Inspection
Elapsed HoursTask HoursNumber of PersonsTask
1.532PART 1
362PART 2
---PART 3 (a)
1.532PART 4
--TOTAL FOR EACH AIRPLANE (b)
(a) The task and elapsed hours are not given as the work necessary for repairs varies depend-
ing on condition.
(b) The total task hours and elapsed hours are not given as the work necessary for each air-
plane is variable.
Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections
and Wire Integrity Tests
Elapsed HoursTask HoursNumber of PersonsTask
---PART 3 (a)
8162PART 5
242PART 6
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Table 2: Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections
and Wire Integrity Tests
Elapsed HoursTask HoursNumber of PersonsTask
242PART 7
242PART 8
1.532PART 9
111PART 10
---PART 11 (a)
111PART 12 (c)
0.750.751PART 13 (c)
0.250.251PART 14 (c)
111PART 15 (c)
111PART 16 (c)
2.752.751PART 17 (c)
1.532PART 18
6122PART 19
1.532PART 20 (b)
1.532PART 21 (b)
---PART 22 (a)
---PART 23 (a)
6122PART 24 (b)
362PART 25 (b)
---PART 26 (a)
6122PART 27 (b)
111PART 28 (c)
---PART 29 (a)
8162PART 30
--TOTAL FOR EACH AIRPLANE (d)
(a) The task and elapsed hours are not given as the work necessary for repairs varies depend-
ing on condition.
(b) This task is done on each engine or engine pylon. Task hours is for all three locations.
(c) The task and elapsed hours are given for one engine only.
(d) The total task hours and elapsed hours are not given as the work necessary for each air-
plane is variable.
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H. Weight and Balance Changes
None.
I. Electrical Load Data
Not changed.
J. References
1. Existing Data:
a. Boeing Service Related Problem (SRP) MD11-78-0117
b. ROHR, Inc Component Maintenance Manual (CMM) 71-50-07
c. MRAS Component Maintenance Manual (CMM) 78-31-35
d. Service Bulletin Index D624N001
e. Standard Overhaul Practices Manual (SOPM) 20-10-24
f. Standard Wiring Practices Manual (SWPM) 20-00-06, 20-00-09, 20-10-01, 20-50-01
g. MD-11 Aircraft Maintenance Manual (AMM) 06-24-00, 20-50-02, 24-00-00, 36-11-07, 36-13-01,
36-13-03, 71-00-00, 71-10-00, 71-50-04, 71-50-05, 76-11-10, 78-30-00, 78-31-10, 78-31-22
h. MD-11 Fleet Team Digest (FTD) 78-23001
i. MD-11 Wiring Diagram Manual (WDM) 71-51-11, 71-51-12, 71-51-13, 78-34-01, 78-34-02,
78-34-03
2. Data Supplied with this Service Bulletin:
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin:
None.
4. Process Data:
Douglas Process Specifications referred to on the drawings are not given in this service bulletin
since these procedures are frequently used as standard shop practices.
K. Publications Affected
1. Publications:
Chapter-SectionPublication
71-50Aircraft Maintenance Manual
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2. Damage Tolerance Based Structural Inspections:
Boeing has evaluated the repairs and/or changes in this service bulletin for effects on Fatigue
Critical Structure (FCS) and for changes to Damage Tolerance Inspections (DTI) required in the
Maintenance Program. This service bulletin does not affect FCS, therefore DTIs are not necessary.
L. Interchangeability and Intermixability of Parts
Accomplishment of this service bulletin does not affect interchangeability or intermixability of parts.
M. Software Accomplishment Summary
Not affected.
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2.    MATERIAL INFORMATION
A. Material - Price and Availability
The operator can supply the parts and materials shown in Paragraph 2.C., Parts Necessary for Each
Airplane.
B. Industry Support Information
Boeing warranty remedies are not available for the configuration changes given in this service bulletin.
C. Parts Necessary for Each Airplane
1. Kits/Parts:
None.
2. Parts and Materials Supplied by the Operator:
The following parts or materials are necessary to do the change in this service bulletin. Parts and
materials in the manuals given in Paragraph 1.J., References, can also be necessary. Examine
operator part and material supply to make sure all necessary parts and materials are available.
NotesExisting Part NumberNameQTYPart Number /
Specification
(a)AUN7613-( )PYLON JUNCTION BOX1AUN7613-( )
(a)AUN8602JUNCTION BOX COVER1AUN8602
(a)(b)224W9721-50( ) OR
224W9921-50( )
CORE MISCELLANEOUS WIRE
HARNESS ASSEMBLY
1224W9721-50( ) OR
224W9921-50( )
(a)(b)224W9731-50( )30 DEGREE BULKHEAD WIRE
HARNESS ASSEMBLY
1224W9731-50( )
(a)(c)7116M20G( )FAN REVERSER ELECTRICAL
CABLE
17116M20G( )
(a)(c)7116M21G( )FAN REVERSER ELECTRICAL
CABLE
17116M21G( )
(d)(e)(f)-CHEMICAL CONVERSION COAT-
ING
0.25
Pt
SOPM 20-10-24
CLASS B, TYPE 2
(a) If necessary. This is the number of parts for one engine.
(b) Can be repaired, refer to Rohr, Inc CMM 71-50-07 as an accepted procedure.
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NotesExisting Part NumberNameQTYPart Number /
Specification
(c) Can be supplied by: Middle River Aerospace Systems (MRAS) (CAGE 5KXN9).
For customers based in the Americas: (including Canada, South America, and the continental US including
the Hawaiian Islands, and the US Territories in the Caribbean and Pacific Territory), contact Middle
River Aerostructure Systems at: Website: https://aerohub.stengg.com/us (If stock is not available, contact
a Customer Account Representative at MRAS_CF6_Customer_Support@mras.com).
For customers based in the Rest of the World, contact ST Engineering Aerospace Systems Pte. Ltd at:
Website: https://aerohub.stengg.com/sg (If stock is not available, contact a Customer Support Repre-
sentative at aerohub_support@stengg.com).
AOG contact: aeroline@stengg.com; AOG Helpline: +1 410-346-0502 or +65 3129-2468 MRAS Customer
Call Center/ Support: aeroline@stengg.com; Helpline: +1 410-346-0502 or +65 3129-2468.
(d) Refer to the Qualified Products List at the end of the Boeing Material Specification (BMS) for supplier
data.
(e) Some conversion coatings contain Chromium trioxide/Chromic acid and will not be available in the Eu-
ropean Union after September 2017 without an authorization. EU operators are encouraged to ensure
their suppliers are authorized to provide the material after the sunset date and that downstream users
comply with the risk mitigation measures and operational conditions.
(f) Aviall (CAGE 22819), 2750 Regent Boulevard, Dallas, Texas 75261
Contact Information: Email: Supplier_Services@Aviall.com, Attention: Product Line Manager, Telephone:
1-800-Aviall-1 or 972-586-1000, Website: http://www.aviall.com.
3. Parts Modified and Reidentified:
None.
4. Parts Removed and Not Replaced:
None.
D. Parts Necessary to Change Spares
None.
E. Special Tooling - Price and Availability
None.
F. Special Tooling Necessary to do this Service Bulletin
No special tools or equipment are necessary to do the change in this service bulletin. But, maintenance
and overhaul tools in the manuals given in Paragraph 1.J., References, can be necessary. Examine
operator tool supply to make sure all necessary tools are available.
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3.    ACCOMPLISHMENT INSTRUCTIONS
A. GENERAL INFORMATION
IF ELECTRICAL POWER IS APPLIED TO THE AIRPLANE, MAKE SURE YOU
OBEY ALL PRECAUTIONS WHILE YOU DO WORK. IF YOU DO NOT OBEY THE
PRECAUTIONS, DEATH OR INJURY TO PERSONS, AND DAMAGE TO THE
AIRPLANE CAN OCCUR.WARNING
ELECTRICALLY GROUND THE AIRPLANE. THIS WILL HELP TO PREVENT
DAMAGE TO THE AIRPLANE OR EQUIPMENT.CAUTION
KEEP THE WORK AREA, WIRES AND ELECTRICAL BUNDLES CLEAN OF
METAL PARTICLES OR CONTAMINATION WHEN YOU USE TOOLS. UNWANTED
MATERIAL, METAL PARTICLES OR CONTAMINATION CAUGHT IN WIRE
BUNDLES CAN CAUSE DAMAGE TO THE BUNDLES. DAMAGED WIRE BUNDLES
CAN CAUSE SPARKS OR OTHER ELECTRICAL DAMAGE.
CAUTION
NOTE: 1. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for
definition of the acronyms.
2. Equivalent parts are listed in the AEPL, Drawing 7595071.
3. The work instructions are divided into work packages. Each work package can be
completed independently during separate maintenance visits. Task Hours and Elapsed
Hours for each work package are given in Paragraph 1.G., Manpower.
4. Unless shown differently, these dimensions and tolerances are used:
– Linear dimensions are in inches
– Tolerance on linear dimensions, other than rivet and bolt edge margins, is plus
or minus 0.03 inch.
– Tolerance on rivet and bolt edge margin is plus or minus 0.05 inch
– Angular tolerance is plus or minus 2 degrees
– Hole dimensions for standard solid rivets are in MD-11 Structural Repair Manual
(SRM) Chapter 51.
– Torque Values:
— Values for structural fasteners are included in Chapter 20 of MD-11 Aircraft
Maintenance Manual (AMM).
— Values for airframe maintenance tasks are included in Chapter 20 of MD-11
Aircraft Maintenance Manual (AMM).
— Values for electrical maintenance tasks are included in Chapter 20 of
Standard Wiring Practices Manual (SWPM).
— Values for engine maintenance tasks are included in Chapter 70 of MD-11
Aircraft Maintenance Manual (AMM).
— Non-standard torque values for maintenance tasks are included in the
applicable installation step.
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5. Refer to the SWPM 20-10-01 as accepted wire installation procedures.
Refer to these SWPM chapters for applicable operations, as accepted procedures:
– TITLECHAPTER
INSPECTION INSTRUCTIONS FOR STANDARD WIRING INSTALLA-
TIONS
SWPM 20-00-06
GENERAL MAINTENANCE PRACTICES - ELECTRICALSWPM 20-00-09
6. Obey all of the warnings and cautions given in the specified manual sections.
7. Refer to APPENDIX A and APPENDIX B for logic diagram(s). Logic diagrams are
provided as an aid only. Information contained in Paragraph 1.E., Compliance is the
primary source for compliance times. Information contained in Paragraph 3.B., Work
Instructions is the primary source for tasks required for compliance.
8. A Detailed Inspection is defined as: An intensive examination of a specific item,
installation, or assembly to detect damage, failure, or irregularity. This could include
tactile assessment in which a component or assembly can be checked for
tightness/security. Available lighting is normally supplemented with a direct source
of good lighting at an intensity deemed appropriate. Inspection aids such as mirrors,
magnifying lenses, borescopes, etc. may be necessary. Surface cleaning and
elaborate procedures may be required.
9. These work instructions refer to procedures included in other Boeing documents.
When the words "refer to" are used and the operator has an accepted alternative
procedure, the accepted alternative procedure can be used. When the words "in
accordance with" are included in the instruction, the procedure in the Boeing document
must be used.
10. If it is necessary to remove more parts for access, you can remove those parts. If
you can get access without removing identified parts, it is not necessary to remove
all of the identified parts. Jacking and shoring limitations must be observed.
11. This service bulletin includes functional test procedures for the systems changed by
this service bulletin. More functional tests can possibly be necessary in accordance
with standard maintenance practices because of interruption to other airplane systems.
12. Use of colors in Figures is based on guidance from the ATA e-Business Program
(ATA) iSpec 2200.
13. When more than one OPTION is given for a CONDITION, do only one of the OPTION
numbers. When more than one ACTION is given for a CONDITION or an OPTION,
do all of the ACTION numbers for that CONDITION or OPTION.
14. The compliance times for the actions in Paragraph 3.B., WORK INSTRUCTIONS
are in Paragraph 1.E., Compliance.
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15. Some steps in the Work Instructions are labeled as Required for Compliance (RC).
If this service bulletin is mandated by an Airworthiness Directive (AD), then the steps
labeled as RC, including sub-steps under an RC step and any figures identified in
an RC step, must be done to comply with the AD. If a step or sub-step is labeled
"RC Exempt," then the RC requirement is removed from that step or sub-step. An
Alternative Method of Compliance (AMOC) is required for any deviations to RC steps,
including sub-steps and identified figures. Steps not labeled as RC may be deviated
from using accepted methods in accordance with the operator's maintenance or
inspection program without obtaining approval of an AMOC. This is provided that
the RC steps, including sub-steps and identified figures, can still be done as specified,
and the airplane can be put back in an airworthy condition.
16. Send to The Boeing Company via Boeing Communication System (BCS) general
information on the inspected airplane, report of found damage, test failures, repairs,
location and nature of damage on the airplane, pylons, engine, and thrust reversers.
Refer to APPENDIX C for additional guidance.
B. WORK INSTRUCTIONS
Work Package 1 - Engine 1, Engine 2, and Engine 3 Pylon Thrust Reverser Control System Wire
Harnesses Detailed Inspection
1. Do PART 1: WORK PACKAGE 1 OPEN ACCESS.
2. RC - Do PART 2: ENGINE 1, ENGINE 2, AND ENGINE 3 PYLON WIRE HARNESS DETAILED
INSPECTION for wire chafing damage, signs of arcing, and riding conditions.
NOTE: Accomplishing the initial ACTION 1 through 3 inclusive specified in Work Package 2
terminates the Work Package 1 PART 2: ENGINE 1, ENGINE 2, AND ENGINE 3 PYLON
WIRE HARNESS DETAILED INSPECTION requirement.
a. CONDITION 1: NO WIRE CHAFING DAMAGE FOUND, NO SIGNS OF ARCING, AND NO
RIDING CONDITIONS FOUND during PART 2: ENGINE 1, ENGINE 2, AND ENGINE 3
PYLON WIRE HARNESS DETAILED INSPECTION.
(1) CONDITION 1 (ACTION 1): Do PART 4: WORK PACKAGE 1 RETURN TO SERVICE
TESTS AND CLOSE ACCESS.
(2) CONDITION 1 (ACTION 2): Do the actions specified in Work Package 2.
b. CONDITION 2: ANY WIRE CHAFING DAMAGE FOUND, ANY SIGNS OF ARCING, OR ANY
RIDING CONDITIONS FOUND during PART 2: ENGINE 1, ENGINE 2, AND ENGINE 3
PYLON WIRE HARNESS DETAILED INSPECTION.
(1) CONDITION 2 (ACTION 1): Do PART 3: WIRE HARNESS REPAIR.
(2) CONDITION 2 (ACTION 2): Do PART 4: WORK PACKAGE 1 RETURN TO SERVICE
TESTS AND CLOSE ACCESS.
(3) CONDITION 2 (ACTION 3): Do the actions specified in Work Package 2.
3. Put the airplane back to a serviceable condition.
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Work Package 2 - Thrust Reverser Control System Wire Harnesses Detailed Inspections and
Wire Integrity Tests
1. Do PART 5: WORK PACKAGE 2 OPEN ACCESS.
2. RC - ACTION 1: Do PART 6: ENGINE 1 THRUST REVERSER CONTROL SYSTEM WIRE
HARNESSES DETAILED INSPECTION AND WIRE INTEGRITY TESTS for wire chafing damage,
riding conditions, signs of arcing, and wire integrity tests failure.
NOTE: Accomplishing ACTION 1 through 3 inclusive terminates the Work Package 1 PART 2
ENGINE 1, ENGINE 2, AND ENGINE 3 PYLON WIRE HARNESS DETAILED
INSPECTION requirement.
NOTE: Wire integrity tests consist of a continuity test and an insulation resistance test.
a. CONDITION 3: NO WIRE CHAFING DAMAGE FOUND, NO RIDING CONDITIONS FOUND,
NO SIGNS OF ARCING FOUND, AND WIRE INTEGRITY TESTS PASSED during PART 6:
ENGINE 1 THRUST REVERSER CONTROL SYSTEM WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRITY TESTS.
(1) Repeat PART 6: ENGINE 1 THRUST REVERSER CONTROL SYSTEM WIRE
HARNESSES DETAILED INSPECTION AND WIRE INTEGRITY TESTS.
b. CONDITION 4: ANY WIRE CHAFING DAMAGE FOUND, ANY RIDING CONDITIONS FOUND,
ANY SIGNS OF ARCING FOUND, OR ANY WIRE INTEGRITY TEST FAILED during PART
6: ENGINE 1 THRUST REVERSER CONTROL SYSTEM WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRITY TESTS.
(1) CONDITION 4 (ACTION 1): Do PART 3: WIRE HARNESS REPAIR.
(2) CONDITION 4 (ACTION 2): Repeat PART 6: ENGINE 1 THRUST REVERSER CONTROL
SYSTEM WIRE HARNESSES DETAILED INSPECTION AND WIRE INTEGRITY TESTS.
3. RC - ACTION 2: Do PART 7: ENGINE 2 THRUST REVERSER CONTROL SYSTEM WIRE
HARNESSES DETAILED INSPECTION AND WIRE INTEGRITY TESTS for wire chafing damage,
riding conditions, signs of arcing, and wire integrity tests failure.
NOTE: Accomplishment of the initial ACTION 1 through 3 inclusive specified in Work Package
2 terminates the Work Package 1 PART 2: ENGINE 1, ENGINE 2, AND ENGINE 3 PYLON
WIRE HARNESS DETAILED INSPECTION requirement.
NOTE: Wire integrity tests consist of a continuity test and an insulation resistance test.
a. CONDITION 5: NO WIRE CHAFING DAMAGE FOUND, NO RIDING CONDITIONS FOUND,
NO SIGNS OF ARCING FOUND, AND WIRE INTEGRITY TESTS PASSED during PART 7:
ENGINE 2 THRUST REVERSER CONTROL SYSTEM WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRITY TESTS.
(1) Repeat PART 7: ENGINE 2 THRUST REVERSER CONTROL SYSTEM WIRE
HARNESSES DETAILED INSPECTION AND WIRE INTEGRITY TESTS.
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b. CONDITION 6: ANY WIRE CHAFING DAMAGE FOUND, ANY RIDING CONDITIONS FOUND,
ANY SIGNS OF ARCING FOUND, OR ANY WIRE INTEGRITY TEST FAILED during PART
7: ENGINE 2 THRUST REVERSER CONTROL SYSTEM WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRITY TESTS.
(1) CONDITION 6 (ACTION 1): Do PART 3: WIRE HARNESS REPAIR.
(2) CONDITION 6 (ACTION 2): Repeat PART 7: ENGINE 2 THRUST REVERSER CONTROL
SYSTEM WIRE HARNESSES DETAILED INSPECTION AND WIRE INTEGRITY TESTS.
4. RC - ACTION 3: Do PART 8: ENGINE 3 THRUST REVERSER CONTROL SYSTEM WIRE
HARNESSES DETAILED INSPECTION AND WIRE INTEGRITY TESTS for wire chafing damage,
riding conditions, signs of arcing, and wire integrity tests failure.
NOTE: Accomplishment of the initial ACTION 1 through 3 inclusive specified in Work Package
2 terminates the Work Package 1 PART 2: ENGINE 1, ENGINE 2, AND ENGINE 3 PYLON
WIRE HARNESS DETAILED INSPECTION requirement.
NOTE: Wire integrity tests consist of a continuity test and an insulation resistance test.
a. CONDITION 7: NO WIRE CHAFING DAMAGE FOUND, NO RIDING CONDITIONS FOUND,
NO SIGNS OF ARCING FOUND, AND WIRE INTEGRITY TESTS PASSED during PART 8:
ENGINE 3 THRUST REVERSER CONTROL SYSTEM WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRITY TESTS.
(1) Repeat PART 8: ENGINE 3 THRUST REVERSER CONTROL SYSTEM WIRE
HARNESSES DETAILED INSPECTION AND WIRE INTEGRITY TESTS.
b. CONDITION 8: ANY WIRE CHAFING DAMAGE FOUND, ANY RIDING CONDITIONS FOUND,
ANY SIGNS OF ARCING FOUND, OR ANY WIRE INTEGRITY TEST FAILED during PART
8: ENGINE 3 THRUST REVERSER CONTROL SYSTEM WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRITY TESTS.
(1) CONDITION 8 (ACTION 1): Do PART 3: WIRE HARNESS REPAIR.
(2) CONDITION 8 (ACTION 2): Repeat PART 8: ENGINE 3 THRUST REVERSER CONTROL
SYSTEM WIRE HARNESSES DETAILED INSPECTION AND WIRE INTEGRITY TESTS.
5. Do PART 9: ENGINE 1, ENGINE 2, AND ENGINE 3 PYLON JUNCTION BOX REMOVAL.
6. RC - On each of the Engine 1, Engine 2, and Engine 3 pylon Junction Box do as follows:
a. ACTION 4: Do PART 10: JUNCTION BOX DETAILED INSPECTION for wire chafing damage
and signs of arcing.
(1) CONDITION 9: NO WIRE CHAFING DAMAGE FOUND AND NO SIGNS OF ARCING
FOUND during PART 10: JUNCTION BOX DETAILED INSPECTION.
(a) Repeat PART 10: JUNCTION BOX DETAILED INSPECTION.
(2) CONDITION 10: ANY WIRE CHAFING DAMAGE FOUND OR ANY SIGNS OF ARCING
FOUND during PART 10: JUNCTION BOX DETAILED INSPECTION.
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(a) CONDITION 10 OPTION 1 (ACTION 1): Do PART 11: JUNCTION BOX REPAIR.
(b) CONDITION 10 OPTION 1 (ACTION 2): Repeat PART 10: JUNCTION BOX
DETAILED INSPECTION.
(c) CONDITION 10 OPTION 2: Do PART 12: JUNCTION BOX REPLACEMENT.
1) CONDITION 10.1: NO WIRE CHAFING DAMAGE FOUND, NO SIGNS OF
ARCING FOUND, CONTINUITY TEST PASSED AND INSULATION
RESISTANCE TEST PASSED during PART 12: JUNCTION BOX
REPLACEMENT.
a) Repeat PART 10: JUNCTION BOX DETAILED INSPECTION.
2) CONDITION 10.2: ANY WIRE CHAFING DAMAGE FOUND, ANY SIGNS OF
ARCING FOUND, ANY CONTINUITY TEST FAILED, OR ANY INSULATION
RESISTANCE TEST FAILED during PART 12: JUNCTION BOX
REPLACEMENT.
a) CONDITION 10.2 OPTION 1 (ACTION 1): Do PART 12: JUNCTION BOX
REPLACEMENT.
b) CONDITION 10.2 OPTION 2 (ACTION 1): Do PART 11: JUNCTION BOX
REPAIR.
c) CONDITION 10.2 OPTION 2 (ACTION 2): Repeat PART 10: JUNCTION
BOX DETAILED INSPECTION.
b. ACTION 5: Do PART 13: JUNCTION BOX COVER DETAILED INSPECTION for burn marks,
signs of arcing, and fretting to the internal surface of the Junction Box Cover.
(1) CONDITION 11: NO BURN MARKS FOUND, NO SIGNS OF ARCING FOUND, AND
NO FRETTING FOUND ON THE INTERNAL SURFACE OF THE JUNCTION BOX
COVER during PART 13: JUNCTION BOX COVER DETAILED INSPECTION.
(a) CONDITION 11 (ACTION 1): Do PART 14: JUNCTION BOX COVER INSTALLATION.
(b) CONDITION 11 (ACTION 2): Repeat PART 13: JUNCTION BOX COVER DETAILED
INSPECTION.
(2) CONDITION 12: ANY BURN MARK FOUND, ANY SIGNS OF ARCING FOUND, OR
FRETTING FOUND ON THE INTERNAL SURFACE OF THE JUNCTION BOX COVER
during PART 13: JUNCTION BOX COVER DETAILED INSPECTION.
(a) CONDITION 12 (ACTION 1): Do PART 15: JUNCTION BOX COVER
REPLACEMENT.
(b) CONDITION 12 (ACTION 2): Repeat PART 13: JUNCTION BOX COVER DETAILED
INSPECTION.
c. ACTION 6: Do PART 16: JUNCTION BOX WIRE INTEGRITY TESTS to test for wire integrity
tests failure.
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NOTE: Wire integrity tests consist of a continuity test and an insulation resistance test.
(1) CONDITION 13: WIRE INTEGRITY TESTS PASSED during PART 16: JUNCTION BOX
WIRE INTEGRITY TESTS.
(a) CONDITION 13 (ACTION 1): Do PART 18: ENGINE 1, ENGINE 2, AND ENGINE 3
PYLON JUNCTION BOX INSTALLATION.
(b) CONDITION 13 (ACTION 2): Repeat PART 16: JUNCTION BOX WIRE INTEGRITY
TESTS.
(2) CONDITION 14: ANY WIRE INTEGRITY TEST FAILED during PART 16: JUNCTION
BOX WIRE INTEGRITY TESTS.
(a) CONDITION 14 OPTION 1 (ACTION 1): Replace the Junction Box.
(b) CONDITION 14 OPTION 1 (ACTION 2): Do PART 17: POST JUNCTION BOX
REPLACEMENT DETAILED INSPECTION AND WIRE INTEGRITY TESTS for burn
marks, signs of arcing, and fretting to the internal surface of the Junction Box cover,
wire chafing damage, signs of arcing, and wire integrity tests failure in the Junction
Box.
NOTE: Wire integrity tests consist of a continuity test and an insulation resistance
test.
1) CONDITION 14.1: NO BURN MARKS, NO SIGNS OF ARCING FOUND, AND
NO FRETTING FOUND ON THE INTERNAL SURFACE OF THE JUNCTION
BOX COVER, AND NO WIRE CHAFING DAMAGE FOUND, NO SIGNS OF
ARCING FOUND, AND WIRE INTEGRITY TESTS PASSED IN THE JUNCTION
BOX during PART 17: POST JUNCTION BOX REPLACEMENT DETAILED
INSPECTION AND WIRE INTEGRITY TESTS.
a) CONDITION 14.1 (ACTION 1): Do PART 14: JUNCTION BOX COVER
INSTALLATION.
b) CONDITION 14.1 (ACTION 2): Repeat PART 16: JUNCTION BOX WIRE
INTEGRITY TESTS.
2) CONDITION 14.2: ANY BURN MARKS, ANY SIGNS OF ARCING FOUND,
AND ANY FRETTING FOUND ON THE INTERNAL SURFACE OF THE
JUNCTION BOX COVER, AND ANY WIRE CHAFING DAMAGE FOUND AND
ANY SIGNS OF ARCING FOUND IN THE JUNCTION BOX during PART 17:
POST JUNCTION BOX REPLACEMENT DETAILED INSPECTION AND WIRE
INTEGRITY TESTS.
a) CONDITION 14.2 (ACTION 1): Do PART 11: JUNCTION BOX REPAIR.
b) CONDITION 14.2 (ACTION 2): Do PART 15: JUNCTION BOX COVER
REPLACEMENT.
c) CONDITION 14.2 (ACTION 3): Repeat PART 16: JUNCTION BOX WIRE
INTEGRITY TESTS.
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### Page 40

3) CONDITION 14.3: ANY BURN MARKS, ANY SIGNS OF ARCING FOUND,
AND ANY FRETTING FOUND ON THE INTERNAL SURFACE OF THE
JUNCTION BOX COVER, AND NO WIRE CHAFING DAMAGE FOUND, NO
SIGNS OF ARCING FOUND, AND WIRE INTEGRITY TESTS PASSED IN THE
JUNCTION BOX during PART 17: POST JUNCTION BOX REPLACEMENT
DETAILED INSPECTION AND WIRE INTEGRITY TESTS.
a) CONDITION 14.3 (ACTION 1): Do PART 15: JUNCTION BOX COVER
REPLACEMENT.
b) CONDITION 14.3 (ACTION 2): Repeat PART 16: JUNCTION BOX WIRE
INTEGRITY TESTS.
4) CONDITION 14.4: NO BURN MARKS, NO SIGNS OF ARCING FOUND, AND
NO FRETTING FOUND ON THE INTERNAL SURFACE OF THE JUNCTION
BOX COVER, AND ANY WIRE CHAFING DAMAGE FOUND OR ANY SIGNS
OF ARCING FOUND IN THE JUNCTION BOX during PART 17: POST
JUNCTION BOX REPLACEMENT DETAILED INSPECTION AND WIRE
INTEGRITY TESTS.
a) CONDITION 14.4 OPTION 1 (ACTION 1): Do PART 11: JUNCTION BOX
REPAIR.
b) CONDITION 14.4 OPTION 1 (ACTION 2): Do PART 14: JUNCTION BOX
COVER INSTALLATION.
c) CONDITION 14.4 OPTION 1 (ACTION 3): Repeat PART 16: JUNCTION
BOX WIRE INTEGRITY TESTS.
d) CONDITION 14.4 OPTION 2 (ACTION 1): Replace the Junction Box.
e) CONDITION 14.4 OPTION 2 (ACTION 2): Do PART 17: POST JUNCTION
BOX REPLACEMENT DETAILED INSPECTION AND WIRE INTEGRITY
TESTS for burn marks, signs of arcing, and fretting to the internal surface
of the Junction Box cover, wire chafing damage, signs of arcing, and wire
integrity tests failure in the Junction Box.
(c) CONDITION 14 OPTION 2 (ACTION 1): Do PART 11: JUNCTION BOX REPAIR.
(d) CONDITION 14 OPTION 2 (ACTION 2): Do PART 14: JUNCTION BOX COVER
INSTALLATION.
(e) CONDITION 14 OPTION 2 (ACTION 4): Repeat PART 16: JUNCTION BOX WIRE
INTEGRITY TESTS.
7. RC - On each Engine (Engine 1, Engine 2, and Engine 3), do as follows:
a. ACTION 7: Do PART 19: LEFT SIDE AND RIGHT SIDE THRUST REVERSER ELECTRICAL
HARNESS DETAILED INSPECTION AND WIRE INTEGRITY TESTS for wire chafing damage,
signs of arcing, and wire integrity tests failure.
NOTE: Wire integrity tests consist of a continuity test, a conductivity test, and an insulation
resistance.
Export Controlled ECCN: 9E991
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(1) CONDITION 15: NO WIRE CHAFING DAMAGE FOUND, NO SIGNS OF ARCING
FOUND, AND WIRE INTEGRITY TESTS PASSED, ON BOTH THE LEFT SIDE AND
RIGHT SIDE THRUST REVERSER ELECTRICAL HARNESS, during PART 19: LEFT
SIDE AND RIGHT SIDE THRUST REVERSER ELECTRICAL HARNESS DETAILED
INSPECTION AND WIRE INTEGRITY TESTS.
(a) Repeat PART 19: LEFT SIDE AND RIGHT SIDE THRUST REVERSER ELECTRICAL
HARNESS DETAILED INSPECTION AND WIRE INTEGRITY TESTS.
(2) CONDITION 16: ANY WIRE CHAFING DAMAGE FOUND, ANY SIGNS OF ARCING
FOUND, OR WIRE INTEGRITY TESTS FAILED ON THE RIGHT SIDE THRUST
REVERSER ELECTRICAL HARNESS during PART 19: LEFT SIDE AND RIGHT SIDE
THRUST REVERSER ELECTRICAL HARNESS DETAILED INSPECTION AND WIRE
INTEGRITY TESTS BUT NO WIRE CHAFING DAMAGE FOUND, NO SIGNS OF ARCING
FOUND, AND WIRE INTEGRITY TESTS PASSED ON THE LEFT SIDE THRUST
REVERSER ELECTRICAL HARNESS.
(a) CONDITION 16 OPTION 1 (ACTION 1): Do PART 20: RIGHT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPLACEMENT.
(b) CONDITION 16 OPTION 1 (ACTION 2): Repeat PART 19: LEFT SIDE AND RIGHT
SIDE THRUST REVERSER ELECTRICAL HARNESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS.
(c) CONDITION 16 OPTION 2 (ACTION 1): Do PART 22: RIGHT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPAIR.
(d) CONDITION 16 OPTION 2 (ACTION 2): Repeat PART 19: LEFT SIDE AND RIGHT
SIDE THRUST REVERSER ELECTRICAL HARNESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS.
(3) CONDITION 17: ANY WIRE CHAFING DAMAGE FOUND, ANY SIGNS OF ARCING
FOUND, OR WIRE INTEGRITY TESTS FAILED ON THE LEFT SIDE THRUST
REVERSER ELECTRICAL HARNESS during PART 19: LEFT SIDE AND RIGHT SIDE
THRUST REVERSER ELECTRICAL HARNESS DETAILED INSPECTION AND WIRE
INTEGRITY TESTS BUT NO WIRE CHAFING DAMAGE FOUND, NO SIGNS OF ARCING
FOUND, AND WIRE INTEGRITY TESTS PASSED ON THE RIGHT SIDE THRUST
REVERSER ELECTRICAL HARNESS.
(a) CONDITION 17 OPTION 1 (ACTION 1): Do PART 21: LEFT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPLACEMENT.
(b) CONDITION 17 OPTION 1 (ACTION 2): Repeat PART 19: LEFT SIDE AND RIGHT
SIDE THRUST REVERSER ELECTRICAL HARNESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS.
(c) CONDITION 17 OPTION 2 (ACTION 1): Do PART 23: LEFT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPAIR.
(d) CONDITION 17 OPTION 2 (ACTION 2): Repeat PART 19: LEFT SIDE AND RIGHT
SIDE THRUST REVERSER ELECTRICAL HARNESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS.
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(4) CONDITION 18: ANY WIRE CHAFING DAMAGE FOUND, ANY SIGNS OF ARCING
FOUND, OR WIRE INTEGRITY TESTS FAILED ON BOTH THE LEFT SIDE AND RIGHT
SIDE THRUST REVERSER ELECTRICAL HARNESSES during PART 19: LEFT SIDE
AND RIGHT SIDE THRUST REVERSER ELECTRICAL HARNESS DETAILED
INSPECTION AND WIRE INTEGRITY TESTS.
(a) CONDITION 18 OPTION 1 (ACTION 1): Do PART 21: LEFT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPLACEMENT.
(b) CONDITION 18 OPTION 1 (ACTION 2): Do PART 20: RIGHT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPLACEMENT.
(c) CONDITION 18 OPTION 1 (ACTION 3): Repeat PART 19: LEFT SIDE AND RIGHT
SIDE THRUST REVERSER ELECTRICAL HARNESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS.
(d) CONDITION 18 OPTION 2 (ACTION 1): Do PART 23: LEFT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPAIR.
(e) CONDITION 18 OPTION 2 (ACTION 2): Do PART 22: RIGHT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPAIR.
(f) CONDITION 18 OPTION 2 (ACTION 3): Repeat PART 19: LEFT SIDE AND RIGHT
SIDE THRUST REVERSER ELECTRICAL HARNESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS.
(g) CONDITION 18 OPTION 3 (ACTION 1): Do PART 23: LEFT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPAIR.
(h) CONDITION 18 OPTION 3 (ACTION 2): Do PART 20: RIGHT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPLACEMENT.
(i) CONDITION 18 OPTION 3 (ACTION 3): Repeat PART 19: LEFT SIDE AND RIGHT
SIDE THRUST REVERSER ELECTRICAL HARNESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS.
(j) CONDITION 18 OPTION 4 (ACTION 1): Do PART 21: LEFT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPLACEMENT.
(k) CONDITION 18 OPTION 4 (ACTION 2): Do PART 22: RIGHT SIDE THRUST
REVERSER ELECTRICAL HARNESS REPAIR.
(l) CONDITION 18 OPTION 4 (ACTION 3): Repeat PART 19: LEFT SIDE AND RIGHT
SIDE THRUST REVERSER ELECTRICAL HARNESS DETAILED INSPECTION
AND WIRE INTEGRITY TESTS.
b. ACTION 8: Do PART 24: CORE MISCELLANEOUS WIRE HARNESS ASSEMBLY DETAILED
INSPECTION AND WIRE INTEGRITY TESTS for wire chafing damage, signs of arcing, and
wire integrity tests failure.
NOTE: Wire integrity tests consist of a continuity test and an insulation resistance test.
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(1) CONDITION 19: NO WIRE CHAFING DAMAGE FOUND, NO SIGNS OF ARCING
FOUND, AND WIRE INTEGRITY TESTS PASSED during PART 24: CORE
MISCELLANEOUS WIRE HARNESS ASSEMBLY DETAILED INSPECTION AND WIRE
INTEGRITY TESTS.
(a) Repeat PART 24: CORE MISCELLANEOUS WIRE HARNESS ASSEMBLY
DETAILED INSPECTION AND WIRE INTEGRITY TESTS.
(2) CONDITION 20: ANY WIRE CHAFING DAMAGE FOUND, ANY SIGNS OF ARCING
FOUND, OR ANY WIRE INTEGRITY TEST FAILED during PART 24: CORE
MISCELLANEOUS WIRE HARNESS ASSEMBLY DETAILED INSPECTION AND WIRE
INTEGRITY TESTS.
(a) CONDITION 20 OPTION 1 (ACTION 1): Do PART 25: CORE MISCELLANEOUS
WIRE HARNESS ASSEMBLY REPLACEMENT.
(b) CONDITION 20 OPTION 1 (ACTION 2): Repeat PART 24: CORE MISCELLANEOUS
WIRE HARNESS ASSEMBLY DETAILED INSPECTION AND WIRE INTEGRITY
TESTS.
(c) CONDITION 20 OPTION 2 (ACTION 1): Do PART 26: CORE MISCELLANEOUS
WIRE HARNESS ASSEMBLY REPAIR.
(d) CONDITION 20 OPTION 2 (ACTION 2): Repeat PART 24: CORE MISCELLANEOUS
WIRE HARNESS ASSEMBLY DETAILED INSPECTION AND WIRE INTEGRITY
TESTS.
c. ACTION 9: Do PART 27: 30 DEGREE BULKHEAD WIRE HARNESS ASSEMBLY DETAILED
INSPECTION AND WIRE INTEGRITY TESTS for wire chafing damage, signs of arcing, and
wire integrity tests failure.
NOTE: Wire integrity tests consist of a continuity test and an insulation resistance test.
(1) CONDITION 21: NO WIRE CHAFING DAMAGE FOUND, NO SIGNS OF ARCING
FOUND, AND WIRE INTEGRITY TESTS PASSED during PART 27: 30 DEGREE
BULKHEAD WIRE HARNESS ASSEMBLY DETAILED INSPECTION AND WIRE
INTEGRITY TESTS.
(a) CONDITION 21 (ACTION 1): Do PART 30: WORK PACKAGE 2 RETURN TO
SERVICE TESTS AND CLOSE ACCESS.
(b) CONDITION 21 (ACTION 2): Repeat PART 26: 30 DEGREE BULKHEAD WIRE
HARNESS ASSEMBLY DETAILED INSPECTION AND WIRE INTEGRITY TESTS.
(2) CONDITION 22: ANY WIRE CHAFING DAMAGE FOUND, ANY SIGNS OF ARCING
FOUND, OR ANY WIRE INTEGRITY TEST FAILED during PART 27: 30 DEGREE
BULKHEAD WIRE HARNESS ASSEMBLY DETAILED INSPECTION AND WIRE
INTEGRITY TESTS.
(a) CONDITION 22 OPTION 1 (ACTION 1): Do PART 28: 30 DEGREE BULKHEAD
WIRE HARNESS ASSEMBLY REPLACEMENT.
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(b) CONDITION 22 OPTION 1 (ACTION 2): Do PART 30: WORK PACKAGE 2 RETURN
TO SERVICE TESTS AND CLOSE ACCESS.
(c) CONDITION 22 OPTION 1 (ACTION 3): Repeat PART 27: 30 DEGREE BULKHEAD
WIRE HARNESS ASSEMBLY DETAILED INSPECTION AND WIRE INTEGRITY
TESTS.
(d) CONDITION 22 OPTION 2 (ACTION 1): Do PART 29: 30 DEGREE BULKHEAD
WIRE HARNESS ASSEMBLY REPAIR.
(e) CONDITION 22 OPTION 2 (ACTION 2): Do PART 30: WORK PACKAGE 2 RETURN
TO SERVICE TESTS AND CLOSE ACCESS.
(f) CONDITION 22 OPTION 2 (ACTION 3): Repeat PART 27: 30 DEGREE BULKHEAD
WIRE HARNESS ASSEMBLY DETAILED INSPECTION AND WIRE INTEGRITY
TESTS.
8. Put the airplane back to a serviceable condition.
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PART 1: WORK PACKAGE 1 OPEN ACCESS
1. Make sure that the thrust reverser on Engine 1, Engine 2, and Engine 3 is fully stowed. Refer to
MD-11 AMM 78-31-22 as an accepted procedure.
2. Remove electrical power from the airplane. Refer to MD-11 AMM 24-00-00 as an accepted
procedure.
3. Open access to the thrust reverser control system wire harnesses as shown in Table 1. Refer to
MD-11 AMM 06-24-00 as an accepted procedure.
Table 1: Open Pylon Access Panels
LOCATIONACCESS NUMBER
LEFT WING PYLON (ENGINE 1)437AL
437AR
437BL
437BR
437DL
437EL
437FL
438AL
438AR
438BL
438CL
438CR
438DL
438GL
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Table 1: Open Pylon Access Panels
LOCATIONACCESS NUMBER
TAIL PYLON (ENGINE 2)457AL
457AR
457BL
457BR
457CL
457CR
457DL
457DR
457EL
457ER
457FR
457GR
RIGHT WING PYLON (ENGINE 3)487AL
487AR
487BL
487BR
487DL
487EL
487FL
488AL
488AR
488BL
488CL
488CR
488DL
488GL
PART 2: ENGINE 1, ENGINE 2, AND ENGINE 3 PYLON WIRE HARNESS DETAILED INSPECTION
1. RC - Do a Detailed Inspection of the Engine 1 pylon thrust reverser control system wire harnesses
for wire chafing damage, signs of arcing, and riding conditions in accordance with FIGURE 1.
2. RC - Do a Detailed Inspection of the Engine 2 pylon thrust reverser control system wire harnesses
for wire chafing damage, signs of arcing, and riding conditions in accordance with FIGURE 2.
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3. RC - Do a Detailed Inspection of the Engine 3 pylon thrust reverser control system wire harnesses
for wire chafing damage, signs of arcing, and riding conditions in accordance with FIGURE 3.
PART 3: WIRE HARNESS REPAIR
1. RC - Repair or replace any wire that has wire chafing damage, signs of arcing, or riding conditions.
Refer to SWPM 20-10-01 as an accepted procedure.
PART 4: WORK PACKAGE 1 RETURN TO SERVICE TESTS AND CLOSE ACCESS
1. RC Exempt - Close access to the thrust reverser control system wire harnesses as shown in Table
2. Refer to MD-11 AMM 06-24-00 as an accepted procedure.
Table 2: Close Pylon Access Panels
LOCATIONACCESS NUMBER
LEFT WING PYLON437AL
437AR
437BL
437BR
437DL
437EL
437FL
438AL
438AR
438BL
438CL
438CR
438DL
438GL
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Table 2: Close Pylon Access Panels
LOCATIONACCESS NUMBER
RIGHT WING PYLON487AL
487AR
487BL
487BR
487DL
487EL
487FL
488AL
488AR
488BL
488CL
488CR
488DL
488GL
TAIL PYLON457AL
457AR
457BL
457BR
457CL
457CR
457DL
457DR
457EL
457ER
457FR
457GR
2. RC Exempt - Restore electrical power to the airplane. Refer to MD-11 AMM 24-00-00 as an
accepted procedure.
3. RC - Do a minimum and approach idle power test and a functional test of the thrust reverser
system. Refer to MD-11 AMM 71-00-00 and MD-11 AMM 78-30-00 as accepted procedures.
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PART 5: WORK PACKAGE 2 OPEN ACCESS
1. Make sure that the thrust reverser on Engine 1, Engine 2, and Engine 3 is fully stowed. Refer to
MD-11 AMM 78-31-22 as an accepted procedure.
2. Remove electrical power from the airplane. Refer to MD-11 AMM 24-00-00 as an accepted
procedure.
3. Open access to the thrust reverser control system wire harnesses as shown in Table 3. Refer to
MD-11 AMM 06-24-00 as an accepted procedure.
Table 3: Open Pylon Access Panels
LOCATIONACCESS NUMBER
LEFT WING PYLON437AL
437AR
437BL
437BR
437DL
437EL
437FL
438AL
438AR
438BL
438CL
438CR
438DL
438GL
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Table 3: Open Pylon Access Panels
LOCATIONACCESS NUMBER
RIGHT WING PYLON487AL
487AR
487BL
487BR
487DL
487EL
487FL
488AL
488AR
488BL
488CL
488CR
488DL
488GL
TAIL PYLON457AL
457AR
457BL
457BR
457CL
457CR
457DL
457DR
457EL
457ER
457FR
457GR
4. On each of the Engine 1 and Engine 3 pylon, do the following:
a. Remove and keep the D1-8051 pneumatic intermediate temperature sensor from the pylon
pneumatic duct. Refer to MD-11 AMM 36-11-07 as an accepted procedure.
b. Remove and keep the D1-8052 pneumatic manifold temperature sensor from the pylon
pneumatic duct. Refer to MD-11 AMM 36-13-03 as an accepted procedure.
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TO PREVENT INJURY AND COMPONENT DAMAGE IT IS RECOMMENDED
THAT TWO TECHNICIANS REMOVE THE BLEED AIR PRECOOLER FROM
THE PYLON.WARNING
DO NOT DISPLACE THE HEADER DUCT SEAL WHEN REMOVING THE
BLEED AIR PRECOOLER.CAUTION
c. Remove the bleed air precooler. Refer to MD-11 AMM 36-13-01 as an accepted procedure.
5. On the Engine 2 pylon, do the following:
MAKE SURE THE INTEGRATED DRIVE GENERATOR (IDG) ELECTRICAL
HARNESS IS PROTECTED AGAINST CHAFING WHEN DOING THE
FOLLOWING PROCEDURES.CAUTION
a. Locate the plenum assembly. Disconnect the wire-harness P-clamps from the plenum assembly.
Remove and keep the bolts and washers from the plenum assembly. Remove and keep the
plenum assembly from the tail pylon. Refer to MD-11 AMM 36-13-01 as an accepted procedure.
b. Remove and keep the D1-8251 pneumatic intermediate temperature sensor from the pylon
pneumatic duct. Refer to MD-11 AMM 36-11-07 as an accepted procedure.
c. Remove and keep the D1-8252 pneumatic manifold temperature sensor from the pylon
pneumatic duct. Refer to MD-11 AMM 36-13-03 as an accepted procedure.
TO PREVENT INJURY AND COMPONENT DAMAGE IT IS RECOMMENDED
THAT TWO TECHNICIANS REMOVE THE BLEED AIR PRECOOLER FROM
THE PYLON.WARNING
DO NOT DISPLACE THE HEADER DUCT SEAL WHEN REMOVING THE
BLEED AIR PRECOOLER.CAUTION
d. Remove the bleed air precooler. Refer to MD-11 AMM 36-13-01 as an accepted procedure.
6. Open the fan cowl and thrust reverser doors. Refer to MD-11 AMM 71-10-00 as an accepted
procedure.
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7. On each of Engine 1, Engine 2, and Engine 3, disconnect the Line Replaceable Units (LRUs)
shown in Table 4.
Table 4: Engine - Line Replaceable Unit (LRU) Disconnection
WIRING DIAGRAMCONNECTORLRU PART NAMELRU
MD-11 WDM 71-51-11P1-8505ATHRUST REVERSER (T/R) DIRECTION-
AL PILOT VALVE
U1-8505
P1-8505B
P1-8506T/R TRANSCOWL INDICATING
SWITCH LEFT HAND SIDE
S1-8506
P1-8508T/R TRANSCOWL INDICATING
SWITCH RIGHT HAND SIDE
S1-8508
P1-8564THRUST REVERSER PRESSURE
REGULATOR AND SHUTOFF VALVE
S2-8564
P1-8157STARTER AIR VALVES2-8157
P1-8564THRUST REVERSER PRESSURE
REGULATOR AND SHUTOFF VALVE
S2-8564
P1-8245ANTI-ICE VALVE INLET COWLS2-8245
P1-8154BYPASS SOLENOID (OUTBOUND)
PRIMARY HYDRAULIC PUMP
S2-8154
P1-8153BYPASS SOLENOID (INBOUND)
STANDBY HYDRAULIC PUMP
S2-8153
P1-8525CHIGH PRESSURE FUEL SHUTOFF
VALVE
U1-8525
P1-8525D
8. On Engine 1 and Engine 3, disconnect the connectors shown in Table 5.
Table 5: Engine 1 and Engine 3 - Connector Disconnection
WIRING DIAGRAMCONNECTOR (RECEPTACLE)CONNECTOR (PLUG)
MD-11 WDM 71-51-11R5-8510P1-8510
R5-8509P1-8509
R5-8057P1-8057
R5-8011P1-8011
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9. On Engine 2, disconnect the connectors shown in Table 6.
Table 6: Engine 2 - Connector Disconnection
WIRING DIAGRAMCONNECTOR (RECEPTACLE)CONNECTOR (PLUG)
MD-11 WDM 71-51-11R5-8510P1-8510
R5-8509P1-8509
R5-8257P1-8257
R5-8211P1-8211
PART 6: ENGINE 1 THRUST REVERSER CONTROL SYSTEM WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRITY TESTS
1. RC - Do a Detailed Inspection of the Engine 1 thrust reverser control system wire harnesses for
wire chafing damage, riding conditions, and signs of arcing in accordance with FIGURE 4.
2. RC - Do a continuity test of the Engine 1 thrust reverser control system wires, shown in Table 7.
Refer to SWPM 20-00-09 as an accepted procedure. The continuity test is failed if the resistance
is more than 10 ohms.
Table 7: Engine 1 - Continuity Test Connectors
WIRING DIA-
GRAM(S)
TOFROMENGINE NUM-
BER PINCONNECTORPINCONNECTOR
MD-11 WDM 78-
34-01
B2R5-5165GR5-59041
MD-11 WDM 78-
34-01
VR5-8057B1R5-5165
GROUND (5028D)UR5-8057 MD-11 WDM 71-
51-11GR5-8057MR5-567
*JR5-8011HR5-8057
GROUND (5028D)*KP1-8011
*AR5-8057MR5-567
*JR5-8011*SR5-8057
TR5-8057NR5-567
*JR5-8011*BR5-8057
*JR5-8057NR5-567
*JR5-8011*KR5-8057
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
53 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

### Page 54

3. RC - Do a Wire Harness Insulation Resistance Test (In-Service Aircraft) on the connectors shown
in Table 8 below. Refer to SWPM 20-00-09 as an accepted procedure. Test voltage range is 500
VDC. The insulation resistance test is failed if the resistance is less than 5 megohms.
a. Connect the High Voltage wire of the Insulation Resistance megohmmeter tool to the pin
location shown in Table 8.
b. Connect the return lead from the meter to all of the other wired contacts in the connector and
backshell noted with pin ID to complete the test circuit.
NOTE: Adjacent sockets can be tested one by one or they can be electrically connected
together to test multiple wires at a time.
Table 8: Engine 1 - Insulation Resistance Test Connectors
WIRING DIAGRAMPINCONNECTORENGINE NUMBER
MD-11 WDM 78-34-01GR5-59041
B1R5-5165
B2R5-5165
MR5-567
NR5-567
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
54 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

### Page 55

PART 7: ENGINE 2 THRUST REVERSER CONTROL SYSTEM WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRITY TESTS
1. RC - Do a Detailed Inspection of the Engine 2 thrust reverser control system wire harnesses for
wire chafing damage, riding conditions, and signs of arcing in accordance with FIGURE 5.
2. RC - Do a continuity test of the Engine 2 thrust reverser control system wires, shown in Table 9.
Refer to SWPM 20-00-09 as an accepted procedure. The continuity test is failed if the resistance
is more than 10 ohms.
Table 9: Engine 2 - Continuity Test Connectors
WIRING DIA-
GRAM(S)
TOFROMENGINE NUM-
BER PINCONNECTORPINCONNECTOR
MD-11 WDM 78-
34-02
B2R5-5266GR5-59052
MD-11 WDM 78-
34-02
VR5-8257B1R5-5266
GROUND (7132D)UR5-8257 MD-11 WDM 71-
51-11GR5-8257AR5-565
*JR5-8211HR5-8257
GROUND (7132D)*KR5-8211
*AR5-8257AR5-565
*JR5-8211*SR5-8257
TR5-8257BR5-565
*JR5-8211*BR5-8257
*JR5-8257BR5-565
*JR5-8211*KR5-8257
3. RC - Do a Wire Harness Insulation Resistance Test (In-Service Aircraft) of the connectors shown
in Table 10 below. Refer to SWPM 20-00-09 as an accepted procedure. Test voltage range is 500
VDC. The insulation resistance test is failed if the resistance is less than 5 megohms.
a. Connect the High Voltage wire of the Insulation Resistance megohmmeter tool to the pin
location shown in Table 10.
b. Connect the return lead from the meter to all of the other wired contacts in the connector and
backshell noted with pin ID to complete the test circuit.
NOTE: Adjacent sockets can be tested one by one or they can be electrically connected
together to test multiple wires at a time.
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
55 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

### Page 56

Table 10: Engine 2 - Insulation Resistance Test Connectors
WIRING DIAGRAMPINCONNECTORENGINE NUMBER
MD-11 WDM 78-34-02GR5-59052
B1R5-5266
B2R5-5266
AR5-565
BR5-565
PART 8: ENGINE 3 THRUST REVERSER CONTROL SYSTEM WIRE HARNESSES DETAILED
INSPECTION AND WIRE INTEGRITY TESTS
1. RC - Do a Detailed Inspection of the Engine 3 thrust reverser control system wire harnesses for
wire chafing damage, riding conditions, and signs of arcing in accordance with FIGURE 6.
2. RC - Do a continuity test of the thrust reverser control system wires, shown in Table 11. Refer to
SWPM 20-00-09 as an accepted procedure. The continuity test is failed if the resistance is more
than 10 ohms.
Table 11: Engine 3 - Continuity Test Connectors
WIRING DIA-
GRAM(S)
TOFROMENGINE NUM-
BER PINCONNECTORPINCONNECTOR
MD-11 WDM 78-
34-03
B2R5-5265GR5-59063
MD-11 WDM 78-
34-03
VR5-8057B1R5-5265
GROUND (6064D)UR5-8057 MD-11 WDM 71-
51-11GR5-8057MR5-570
*JR5-8011HR5-8057
GROUND (6064D)*KR5-8011
*AR5-8057MR5-570
*JR5-8011*SR5-8057
TR5-8057NR5-570
*JR5-8011*BR5-8057
*JR5-8057NR5-570
*JR5-8011*KR5-8057
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
56 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

### Page 57

3. RC - Do a Wire Harness Insulation Resistance Test (In-Service Aircraft) of the connectors shown
in Table 12 below. Refer to SWPM 20-00-09 as an accepted procedure. Test voltage range is 500
VDC. The insulation resistance test is failed if the resistance is less than 5 megohms.
a. Connect the High Voltage wire of the Insulation Resistance megohmmeter tool to the pin
location shown in Table 12.
b. Connect the return lead from the meter to all of the other wired contacts in the connector and
backshell noted with pin ID to complete the test circuit.
NOTE: Adjacent sockets can be tested one by one or they can be electrically connected
together to test multiple wires at a time.
Table 12: Engine 3 - Insulation Resistance Test Connectors
WIRING DIAGRAMPINCONNECTORENGINE NUMBER
MD-11 WDM 78-34-03GR5-59063
B1R5-5265
B2R2-5265
MR5-570
NR5-570
PART 9: ENGINE 1, ENGINE 2, AND ENGINE 3 PYLON JUNCTION BOX REMOVAL
1. Disconnect the electrical connectors from the Engine 1 pylon Junction Box in accordance with
FIGURE 7.
2. Remove the Junction Box from the Engine 1 pylon in accordance with FIGURE 8.
3. Remove the Engine 1 Junction Box Cover. Refer to FIGURE 11 as an accepted procedure.
4. Disconnect the electrical connectors from the Engine 2 pylon Junction Box in accordance with
FIGURE 9.
5. Remove the Junction Box from the Engine 2 pylon in accordance with FIGURE 10.
6. Remove the Engine 2 Junction Box Cover. Refer to FIGURE 11 as an accepted procedure.
7. Disconnect the electrical connectors from the Engine 3 pylon Junction Box in accordance with
FIGURE 7.
8. Remove the Junction Box from the Engine 3 pylon in accordance with FIGURE 8.
9. Remove the Engine 3 Junction Box Cover. Refer to FIGURE 11 as an accepted procedure.
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
57 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

### Page 58

PART 10: JUNCTION BOX DETAILED INSPECTION
1. RC - Do a Detailed Inspection of the Junction Box for wire chafing damage and signs of arcing in
accordance with FIGURE 12.
PART 11: JUNCTION BOX REPAIR
1. RC - Repair or replace damaged wires in the Junction Box. Refer to SWPM 20-10-01 as an
accepted procedure.
PART 12: JUNCTION BOX REPLACEMENT
1. RC - Replace the Junction Box.
a. Do a continuity test of the contacts in the junction box. The continuity test is failed if the
resistance is more than 10 ohms. Refer to SWPM 20-00-09 as an accepted procedure.
(1) For Engine 1 and Engine 3, refer to MD-11 WDM 71-51-12 for the contacts.
(2) For Engine 2, refer to MD-11 WDM 71-51-13 for the contacts.
b. Do a 500 VDC insulation resistance test to adjacent contacts and shell on the Junction Box.
The insulation resistance test is failed if the resistance is less than 5 megohms. Refer to
SWPM 20-00-09 as an accepted procedure.
c. RC Exempt - Remove the Junction Box Cover. Refer to FIGURE 11 as an accepted procedure.
d. Do a Detailed Inspection of the Junction Box for wire chafing damage and signs of arcing in
accordance with FIGURE 12.
PART 13: JUNCTION BOX COVER DETAILED INSPECTION
1. RC - Do a Detailed Inspection for burn marks, signs of arcing, and fretting to the internal surface
of the Junction Box Cover in accordance with FIGURE 13.
PART 14: JUNCTION BOX COVER INSTALLATION
1. RC - Install the kept Junction Box Cover in accordance with FIGURE 14.
PART 15: JUNCTION BOX COVER REPLACEMENT
1. RC - Install a new Junction Box Cover in accordance with FIGURE 15.
PART 16: JUNCTION BOX WIRE INTEGRITY TESTS
1. RC - Do a continuity test of the pins in the pylon junction box. The continuity test is failed if the
resistance is more than 10 ohms. Refer to SWPM 20-00-09 as an accepted procedure.
a. For Engine 1 and Engine 3, refer to MD-11 WDM 71-51-12 for the connectors and pins.
b. For Engine 2, refer to MD-11 WDM 71-51-13 for the connectors and pins.
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
58 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

### Page 59

2. RC - Do a 500 VDC insulation resistance test to adjacent contacts and shell on the Junction Box.
The insulation resistance test is failed if the resistance is less than 5 megohms. Refer to SWPM
20-00-09 as an accepted procedure.
PART 17: POST JUNCTION BOX REPLACEMENT DETAILED INSPECTION AND WIRE INTEGRITY
TESTS
1. RC - Do a continuity test of the contacts in the junction box. The continuity test is failed if the
resistance is more than 10 ohms. Refer to SWPM 20-00-09 as an accepted procedure.
a. For Engine 1 and Engine 3, refer to MD-11 WDM 71-51-12 for the contacts.
b. For Engine 2, refer to MD-11 WDM 71-51-13 for the contacts.
2. RC - Do a 500 VDC insulation resistance test to adjacent contacts and shell on the Junction Box.
The insulation resistance test is failed if the resistance is less than 5 megohms. Refer to SWPM
20-00-09 as an accepted procedure.
3. RC Exempt - Remove the Junction Box Cover. Refer to FIGURE 11 as an accepted procedure.
4. RC - Do a Detailed Inspection of the Junction Box for wire chafing damage and signs of arcing in
accordance with FIGURE 12.
5. RC - Do a Detailed Inspection of the Junction Box cover for burn marks, signs of arcing, and fretting
to the internal surface of the Junction Box Cover in accordance with FIGURE 13.
PART 18: ENGINE 1, ENGINE 2, AND ENGINE 3 PYLON JUNCTION BOX INSTALLATION
1. RC - Install the Engine 1 pylon Junction Box in accordance with FIGURE 16.
2. RC - Install the Engine 2 pylon Junction Box in accordance with FIGURE 17.
3. RC - Install the Engine 3 pylon Junction Box in accordance with FIGURE 16.
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
59 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

### Page 60

PART 19: LEFT SIDE AND RIGHT SIDE THRUST REVERSER ELECTRICAL HARNESS DETAILED
INSPECTION AND WIRE INTEGRITY TESTS
1. RC - Do a Detailed Inspection of the Left Side and Right Side Thrust Reverser Electrical Harnesses
for any wire chafing damage and any signs of arcing in accordance with FIGURE 18.
2. RC - Do a continuity test of the Left Side and Right Side Thrust Reverser Electrical Harnesses as
follows:
a. Set the ohmmeter to OHMS and set the range control to the R x 1 ohms range. Zero the
ohmmeter.
DO NOT PUT AN OVERSIZED TEST PROBE IN THE CONTACT SOCKET
OF THE CONNECTOR. THIS COULD DAMAGE A CONTACT SOCKET. DO
NOT HANG A TEST LEAD FROM THE CONTACT PIN. THIS COULD
DAMAGE THE CONTACT PIN.CAUTION
b. Do a continuity test of the wire lengths in Table 13 by measuring the pin(contact) to pin(contact)
resistance of every line in the table. The continuity test is failed if the resistance is more than
0.6 ohm.
Table 13: Engine - Right Side Thrust Reverser Electrical Harness Continuity Test Connectors
NOTESWIRING DIAGRAMTOFROM
PINCONNECTORPINCONNECTOR
(a)MD-11 WDM 71-
51-11
BP1-81619R5-8510
(a)A10
-3P1-85082
-43
-54
-65
-106
-18
-811
-712
-214
-913
(a) If connected.
Export Controlled ECCN: 9E991
BOEING PROPRIETARY - See page 1 for details
Original Issue: December 04, 2023
MD11-78A017
60 of 201
BOEING SERVICE BULLETIN MD11-78A017
ALERTALERT

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