# Boeing Alert Service Bulletin 757-28A0078: U.S. DOT/FAA - Service Bulletin (2)

- Rights: © The Boeing Company. Filed by the FAA in regulations.gov docket FAA-2009-0908; AD 2012-06-06 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.
- Document: [Boeing Alert Service Bulletin 757-28A0078](https://openairdocs.org/service-documents/boeing/757-28a0078.md)
- Title as filed: U.S. DOT/FAA - Service Bulletin (2)
- Pages: 47
- PDF: https://openairdocs.org/files/sha256/a5/df/a5df5a0fb48ecb2332e703779e0f3e488b7bf04a9b2651b6aa1a14905854457b
- Page: https://openairdocs.org/service-documents/boeing/757-28a0078/file/a5df5a0fb48e

## Text

Some pages are OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N.

### Page 1

Commercial 
Airplanes
757
Service Bulletin
Number: 757-28A0078
Original Issue: July 16, 2008
Revision 1: August 24, 2010
ATA System: 2822
SUBJECT: FUEL - Engine Fuel Feed System - Fuel Pump Control Ground Fault Interrupter (GFI)
Relay Installation
Export of this technology is controlled under the United States Export Administration Regulations (EAR) (15
CFR 730-774). An export license may be required before it is used for development, production or use by foreign
persons from specific countries. The controller of this data has the individual responsibility to abide by all export
laws.
9E991ECCN:
BOEING PROPRIETARY, CONFIDENTIAL, AND/OR TRADE SECRET
Copyright © 2008 The Boeing Company
Unpublished Work - All Rights Reserved
Boeing claims copyright in each page of this document only to the extent that the page contains copyrightable
subject matter. Boeing also claims copyright in this document as a compilation and/or collective work.
This document includes proprietary information owned by The Boeing Company and/or one or more third parties.
Treatment of the document and the information it contains is governed by contract with Boeing. For more
information, contact The Boeing Company, P.O. Box 3707, Seattle, Washington 98124.
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, KDC-10, MD-10, MD-11, MD-80, MD-88, MD-90, P-8A, Poseidon and the
Boeing livery 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.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
1 of 47
3.0

### Page 2

BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
2 of 47
BOEING SERVICE BULLETIN 757-28A0078
BLANK PAGE

### Page 3

Table of Contents
Revision Transmittal Sheet ............................................ 5
Summary ...................................................... 7
1. PLANNING INFORMATION ........................................ 9
A. Effectivity ................................................ 9
1. Airplanes ............................................. 9
2. Spares Affected ........................................ 1 2
B. Concurrent Requirements ...................................... 1 2
C. Reason ................................................ 1 2
D. Description .............................................. 1 3
E. Compliance .............................................. 1 4
F. Approval ............................................... 1 4
G. Manpower .............................................. 1 4
H. Weight and Balance Changes .................................... 1 5
I. Electrical Load Data ......................................... 1 5
J. References .............................................. 1 5
1. Existing Data: ......................................... 1 5
2. Data supplied with this Service Bulletin: ........................... 1 6
3. Installation Drawings Used in the Preparation of this Service Bulletin: ........... 1 6
K. Publications Affected ........................................ 1 6
L. Interchangeability and Intermixability of Parts ........................... 1 7
2. MATERIAL INFORMATION ........................................ 1 9
A. Material - Price and Availability ................................... 1 9
B. Industry Support Information .................................... 1 9
C. Parts Necessary For Each Airplane ................................. 1 9
1. Kits/Parts: ........................................... 1 9
2. Parts and Materials Supplied by the Operator: ........................ 1 9
3. Parts Modified and Reidentified: ............................... 1 9
4. Parts Removed and Not Replaced: .............................. 1 9
D. Parts Necessary to Change Spares ................................. 1 9
E. Special Tooling - Price and Availability ............................... 1 9
F. Special Tooling Necessary to do this Service Bulletin ....................... 2 0
3. ACCOMPLISHMENT INSTRUCTIONS .................................. 2 1
A. GENERAL INFORMATION ..................................... 2 1
B. WORK INSTRUCTIONS ....................................... 2 2
FIGURE 1: P33 PANEL PLATE 'C' - RELAY REPLACEMENT ...................... 3 9
FIGURE 2: P37 PANEL PLATE 'B' - RELAY REPLACEMENT ...................... 4 1
FIGURE 3: FUEL BOOST PUMP CONTROL GROUND FAULT INTERRUPTER (GFI) RELAY SCHEMATIC
REFERENCE .......................................... 4 3
FIGURE 4: ELECTRICAL BONDING RESISTANCE CHECK FOR GROUND FAULT INTERRUPTER (GFI)
RELAYS, P33 PANEL ..................................... 4 4
FIGURE 5: ELECTRICAL BONDING RESISTANCE CHECK FOR GROUND FAULT INTERRUPTER (GFI)
RELAYS, P37 PANEL ..................................... 4 6
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
3 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 4

BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
4 of 47
BOEING SERVICE BULLETIN 757-28A0078
BLANK PAGE

### Page 5

Commercial 
Airplanes
757
Service Bulletin
Revision Transmittal SheetNumber: 757-28A0078Original Issue: July 16, 2008
Revision 1: August 24, 2010
ATA System: 2822
SUBJECT: FUEL - Engine Fuel Feed System - Fuel Pump Control Ground Fault Interrupter (GFI)
Relay Installation
This revision includes all pages of the service bulletin.
COMPLIANCE INFORMATION RELATED TO THIS REVISION
More work is necessary on airplanes changed in accordance with the original issue of this service bulletin. Do
a General Visual Inspection of the installation screws for the GFI relays K187, K10011, K190, on Plate C of the
P33 Panel and the installation screws for the GFI relays K188, K189, K10012, on Plate B of the P37 Panel to
ensure the necessary grip length screw was used. More work is necessary to measure the electrical bonding
resistance between the GFI Relays and the P33 Panel, Plate C, and to measure the electrical bonding resistance
between the GFI Relays and the P37 Panel, Plate B.
REASON FOR REVISION
This Revision 1 is sent to tell operators that the screws used to install the relays in FIGURE 1 have been changed
from NAS1801-08-5 to NAS1801-08-7. Substitution information for the installation screws was added to FIGURE
2. This revision also provides a new electrical bonding resistance check of the GFI relays installed on the P33
and the P37 Panels.
These sections were changed:
1. Revised Paragraph 1.C., Reason to add the reason for Revision 01.
2. Revised Paragraph 1.D., Description to add 'More work is necessary' note and the maintenance zones
table.
3. Revised Paragraph 1.J., References to add 757-200 SRM 51-40-02, 757-200CB SRM 51-40-02 , 757-200PF
SRM 51-40-02, 757-200CB SRM 51-40-03, 757-200PF SRM 51-40-03, 757-200 SRM 51-40-03, and added
a table for installation drawings used in Paragraph 1.J.3.
4. Revised Paragraph 1.K., Publications Affected to add the Damage Tolerance Inspection note.
5. Revised Paragraph 3.A., General Information to add general notes for fastener installation and substitution.
6. Revised Paragraph 3.B., Work Instructions to add the existing work instructions to a new PART 1 and new
steps 3.B.7 and 3.B.8. Also added new PART 2.
7. Revised FIGURE 1 step table to add new sub-steps.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
5 of 47

### Page 6

8. Revised FIGURE 2 step table to add optional fastener information. New sub-steps were added.
9. Added FIGURE 4 to provide instructions for measuring the electrical bonding resistance between the GFI
relays K187, K10011, K190, on the P33 Panel, and Plate C.
10. Added FIGURE 5 to provide instructions for measuring the electrical bonding resistance between the GFI
relays K188, K189, K10012, on the P37 Panel, and Plate B.
The data given in Information Notice 757-28A0078 R00 IN01 is included in this revision.
Vertical lines are put on the left edge of each page, except in Paragraph 1.A., Effectivity, to show the location
of important changes.
REVISION HISTORY
July 16, 2008Original Issue:
August 24, 2010Revision 1:
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
6 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 7

Commercial 
Airplanes
757
Service Bulletin
SummaryNumber: 757-28A0078Original Issue: July 16, 2008
Revision 1: August 24, 2010
ATA System: 2822
SUBJECT: FUEL - Engine Fuel Feed System - Fuel Pump Control Ground Fault Interrupter (GFI)
Relay Installation
CONCURRENT REQUIREMENTS
None.
BACKGROUND
This service bulletin gives the instructions to replace the power control relays for the fuel boost pumps and
override pumps. The relays are located in the P33 and P37 equipment panels in the main equipment center.
The new relays include a ground fault interrupt (GFI) feature. The GFI relay feature will protect the fuel pumps
from damage caused by electrical arcing because the electrical power will be removed from the pump if a ground
fault is detected. Electrical arcing could create a possible source of ignition of flammable fuel vapors in the fuel
tanks. Ignition of flammable fuel vapors could cause a fire or explosion which could put the airplane in an unsafe
condition.
This service bulletin is the result of the safety assessments conducted by Boeing under SFAR 88, "Fuel Tank
System Fault Tolerance Evaluation Requirements".
This change affects section 9 of the Maintenance Planning Data (MPD) Document. New Airworthiness Limitations
(AWL) "28-AWL-21" will be added to section 9 of the MPD to include a functional check of the ground fault
interrupt (GFI) relays for the fuel boost pumps and override pumps.
The related 757-300 airplane service bulletin number is 757-28A0079.
ACTION (PRR 55000-10RS)
Get access to the main equipment center. At the P33 and P37 panels, replace six relays. Check the electrical
bonding resistance between the GFI relays and the P33 Panel, Plate C, and P37 Panel, Plate B. Do an operational
test of the fuel boost pumps.
EFFECTIVITY
See Service Bulletin Paragraph 1.A.1. for effectivity.
COMPLIANCE
Boeing recommends that operators incorporate the changes shown in this service bulletin within 60 months of
the date on the service bulletin.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
7 of 47

### Page 8

INDUSTRY SUPPORT INFORMATION
Boeing warranty remedies are not available for the configuration changes given in this service bulletin.
MANPOWER
Elapsed HoursTotal Task Hours
6.08.0
MATERIAL INFORMATION
Operator Supplied Parts/Materials.
Refer to Paragraph 2.A., Material - Price and Availability.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
8 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 9

Commercial 
Airplanes
757
Service Bulletin
Number: 757-28A0078
Original Issue: July 16, 2008
Revision 1: August 24, 2010
ATA System: 2822
SUBJECT: FUEL - Engine Fuel Feed System - Fuel Pump Control Ground Fault Interrupter (GFI)
Relay Installation
1.    PLANNING INFORMATION
A. Effectivity
1. Airplanes
Refer to Service Bulletin Index Document D624N001 Part 3 for Airplane Variable Number, Line
Number, and Serial Number data.
This service bulletin is for the airplanes shown below. An equivalent change is on subsequent
production airplanes. Refer to PRR55000-10RS for data about this change.
DESCRIPTIONCONFIGURATIONGROUP
All 757-200, 757-200CB, and 757-200PF airplanes.-1
Airplane Models:
757-200, 757-200CB, 757-200PF
GroupVariable Number
1NA001 - NA028
1NA191 - NA199
1NA201 - NA239
1NA301 - NA305
1NA341 - NA352
1NA391 - NA399
1NA401 - NA408
1NA441 - NA447
1NA501 - NA586
1NB001 - NB004
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
9 of 47

### Page 10

GroupVariable Number
1NB021 - NB023
1NB036 - NB041
1NB051 - NB053
1NB061 - NB073
1NB079
1NB131 - NB148
1NB161 - NB162
1NB166 - NB168
1NB201 - NB204
1NB221 - NB228
1NB230
1NB236
1NB239
1NB261 - NB267
1NB291 - NB299
1NB301 - NB302
1NB311 - NB312
1NB321 - NB331
1NB421 - NB438
1NB446
1NB451 - NB454
1NB501 - NB523
1NB561
1NB571
1NB581 - NB583
1NC001 - NC033
1NC041 - NC042
1NC051 - NC052
1NC056 - NC062
1NC066 - NC084
1NC091 - NC094
1NC151
1NC161
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
10 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 11

GroupVariable Number
1NC901 - NC951
1NC971 - NC974
1ND001 - ND007
1ND011 - ND059
1ND111 - ND113
1ND161 - ND199
1ND201 - ND203
1ND221 - ND225
1ND241 - ND248
1ND301 - ND322
1ND401
1ND891
1ND895
1NE001 - NE008
1NE011 - NE088
1NE091 - NE094
1NE141 - NE150
1NE161 - NE177
1NE201 - NE204
1NE301 - NE302
1NE311 - NE325
1NJ001 - NJ004
1NJ031 - NJ032
1NJ551 - NJ555
1NN001 - NN002
1NN051 - NN052
1NP901 - NP904
1NS601 - NS616
1NT001 - NT009
1NT201 - NT202
1NT231 - NT234
1NT237 - NT240
1NT242
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
11 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 12

GroupVariable Number
1NT245 - NT248
1NT281 - NT289
1NT341 - NT347
1NT351 - NT360
1NT371 - NT373
1NT375 - NT379
1NT381 - NT386
1NT401 - NT409
1NT411 - NT412
1NT426 - NT427
1NT431 - NT432
1NT436 - NT438
1NT441 - NT442
1NT446
1NT701 - NT769
1NT791 - NT796
1NT861 - NT862
1NT881 - NT885
1NT901 - NT916
1NT971 - NT985
1NU031 - NU038
2. Spares Affected
None.
B. Concurrent Requirements
None.
C. Reason
This service bulletin gives the instructions to replace the power control relays for the fuel boost pumps
and override pumps. The relays are located in the P33 and P37 equipment panels in the main equipment
center. The new relays include a ground fault interrupt (GFI) feature. The GFI relay feature will protect
the fuel pumps from damage caused by electrical arcing because the electrical power will be removed
from the pump if a ground fault is detected. Electrical arcing could create a possible source of ignition
of flammable fuel vapors in the fuel tanks. Ignition of flammable fuel vapors could cause a fire or
explosion which could put the airplane in an unsafe condition.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
12 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 13

This service bulletin is the result of the safety assessments conducted by Boeing under SFAR 88, "Fuel
Tank System Fault Tolerance Evaluation Requirements".
This change affects section 9 of the Maintenance Planning Data (MPD) Document. New Airworthiness
Limitations (AWL) "28-AWL-21" will be added to section 9 of the MPD to include a functional check of
the ground fault interrupt (GFI) relays for the fuel boost pumps and override pumps.
The related 757-300 airplane service bulletin number is 757-28A0079.
Revision 01 is sent to tell operators that the screws used to the install the relays in FIGURE 1 have
been changed from NAS1801-08-5 to NAS1801-08-7. Substitution information for the installation screws
was added to FIGURE 2. This revision also provides a new electrical bonding resistance check of the
GFI relays on both the P33 and P37 Panels.
These sections were changed:
1. Revised Paragraph 1.C., Reason to add the reason for Revision 01.
2. Revised Paragraph 1.D., Description to add 'More work is necessary' note and the maintenance
zones table.
3. Revised Paragraph 1.J., References to add 757-200 SRM 51-40-02, 757-200CB SRM 51-40-02
, 757-200PF SRM 51-40-02, 757-200CB SRM 51-40-03, 757-200PF SRM 51-40-03, 757-200 SRM
51-40-03, and added a table for installation drawings used... in Paragraph 1.J.3..
4. Revised Paragraph 1.K., Publications Affected to add the Damage Tolerance Inspection note.
5. Revised Paragraph 3.A., General Information to add general notes for fastener installation and
substitution.
6. Revised Paragraph 3.B., Work Instructions to add the existing work instructions to a new PART 1
and new steps 3.B.1.PART 1.7 and 8. Also added new PART 2.
7. Revised FIGURE 1 step table to add new sub-steps.
8. Revised FIGURE 2 step table to add optional fastener information. New sub-steps were added.
9. Added FIGURE 4 to show where to take electrical bonding resistance check readings for the GFI
relays K187, K10011, K190, on the P33 Panel, Plate C.
10. Added FIGURE 5 to show where to take electrical bonding resistance check readings for the GFI
relays K188, K189, K10012, on the P37 Panel, Plate B.
The data given in Information Notice 757-28A0078 IN 01 is included in this revision.
D. Description
Get access to the main equipment center. At the P33 and P37 panels, replace six relays. Check the
electrical bonding resistance of the GFI relays for the P33 and P37 Panels. Do an operational test ofthe
fuel boost pumps.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
13 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 14

Revision 1 - More work is necessary on airplanes changed in accordance with the original issue of this
service bulletin. Do a General Visual Inspection of the installation screws for the GFI relays K187,
K10011, K190, on Plate C of the P33 Panel and the installation screws for the GFI relays K188, K189,
K10012, on Plate B of the P37 Panel to ensure the necessary grip length screw was used. More work
is necessary to measure the electrical bonding resistance between the GFI Relays and the P33 Panel,
Plate C and measure the electrical bonding resistance between the GFI Relays and the P37 Panel,
Plate B.
The work in this service bulletin is done in the maintenance zone(s) given below.
Affected Maintenance Zones
ZoneModel
119757-200, 757-200CB, 757-
200PF
E. Compliance
Boeing recommends that operators incorporate the changes shown in this service bulletin within 60
months of the date on the service bulletin.
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, as well as European
Aviation Safety Agency (EASA)/Joint Aviation Authorities (JAA) approved for all EASA/JAA approved
airplanes listed in the service bulletin effectivity. 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 table below shows an estimate of the task-hours necessary to do this change for each airplane.
This estimate is for direct labor only, done by an experienced crew. Adjust the estimate with 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.
Elapsed HoursTask-HoursNumber of Per-
sons
Task
0.750.751Open Access
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
14 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 15

Elapsed HoursTask-HoursNumber of Per-
sons
Task
2.52.51Change
0.750.751Close Access
2.04.02Test
6.08.0TOTAL FOR EACH AIRPLANE
H. Weight and Balance Changes
Change in Moment
(Pound-Inches)
Change in Weight
(Pounds)
Airplane
+ 640.0+ 1.6757-200
I. Electrical Load Data
1. Direct Current (DC) Loads:
None
2. Alternating Current (AC) Loads
BusPhaseVolt-Ampere-
Reactive
(VARs)
WattsAirplanes
115V AC BUS LEFT - SECTION 1C0.52- 0.53757-200
115V AC BUS LEFT - SECTION 3C1.04- 1.06757-200
115V RIGHT AC TRANSFER BUSC0.52- 0.53757-200
115V AC GROUND SERVICE BUSC0.52- 0.53757-200
115V AC BUS RIGHT - SECTION 3C0.52- 0.53757-200
3. Type
Continuous
J. References
1. Existing Data:
a. Engineering Change Memo PRR 55000-10RS
b. Standard Overhaul Practices Manual (SOPM) SOPM 20-11-03
c. Standard Wiring Practices Manual (SWPM) 20-10-11, 20-10-12, 20-10-19, 20-20-00, 20-50-10
d. 757 Aircraft Maintenance Manual (AMM) 06-44-00, 24-22-00, 24-31-01, 24-31-03, 28-22-03,
28-26-00
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
15 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 16

e. 757-200 Structural Repair Manual (SRM) 51-40-02, 51-40-02, 51-40-03, 51-40-05
f. 757-200CB Structural Repair Manual (SRM) 51-40-02, 51-40-03, 51-40-05
g. 757-200PF Structural Repair Manual (SRM) 51-40-02, 51-40-03, 51-40-05
2. Data supplied with this Service Bulletin:
None.
3. Installation Drawings Used in the Preparation of this Service Bulletin:
TitleDrawing Number
SHIELD INSTL-MISC ELEC EQUIP P33284N1325
SHIELD INSTL-MISC ELEC EQUIP P37284N1526
SHIELD ASSY-MISC ELEC EQUIP P33284N1318
PANEL ASSY-RIGHT MISC. RELAY, P37284N1127
K. Publications Affected
1. Publications:
Chapter-SectionPublication
28-22757 Wiring Diagram Manual
28-22757 Fault Isolation Manual
28-22757 Illustrated Parts Catalog
Section 9757 Maintenance Planning Document
28-22757 System Schematic Manual
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.
Chapter-SectionPublication
28-22757 Maintenance Manual
28-22757 Wiring Diagram Manual
28-22757 Fault Isolation Manual
28-22757 Illustrated Parts Catalog
28-22757 Schematic Diagram Manual`
Section 9757 Maintenance Planning Document
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
16 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 17

L. Interchangeability and Intermixability of Parts
Refer to Paragraph 2.C., Parts Necessary For Each Airplane, for interchangeability and intermixability
information.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
17 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 18

BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
18 of 47
BOEING SERVICE BULLETIN 757-28A0078
BLANK PAGE

### Page 19

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 and Paragraph 2.D., Parts Necessary to Change Spares. As an alternative, operators can
purchase the parts from Boeing Spares. This service bulletin does not show the Boeing price and
supply data.
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:
NotesExisting Part NumberNameQTYPart Number /
Specification
(a)MS27418-2ARelay69324G-10676
(b)n/aScrew24NAS1801-08-7
(a) Leach International North America (V58657) 6900 Orangethorpe Avenue, P.O. Box 5032, Buena Park,
CA 90622-5032 Phone: (714) 739-0770 Fax:(714) 670-1145
(b) For procurement data use PROCUREMENT SPECIFICATION: MIL-B-87114, except as noted in
NAS1801.
3. Parts Modified and Reidentified:
None.
4. Parts Removed and Not Replaced:
NotesQTYNameExisting Part
Number
6RelayMS27418-2A
12ScrewNAS1801-08-5
D. Parts Necessary to Change Spares
None.
E. Special Tooling - Price and Availability
None.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
19 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 20

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.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
20 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 21

3.    ACCOMPLISHMENT INSTRUCTIONS
A. GENERAL INFORMATION
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.
NOTE: 1. The instructions identified in Paragraph 3.B., Work Instructions, and the Figure(s)
give the recommended sequence of steps. The sequence of steps to do this service
bulletin can be changed.
2. Manual titles are referred to by acronyms. Refer to Paragraph 1.J., References, for
definition of the acronyms.
3. Obey all of the warnings and cautions given in the specified manual sections.
4. Use the approved fastener and process material substitutions in accordance with
757-200 SRM 51-40-02, 757-200CB SRM 51-40-02 and 757-200PF SRM 51-40-02.
Alternate fasteners are listed in 757-200 SRM 51-40-03, 757-200CB SRM 51-40-03
and 757-200PF SRM 51-40-03 and Boeing Drawing 757 65-88700.
5. Refer to the SWPM 20-10-11 and SWPM 20-10-12 for the wire installation procedures,
and SWPM 20-10-19 for the wire separation requirements, as accepted procedures.
6. If the length of any fastener specified in this service bulletin does not meet the
installation standards in 757-200 SRM 51-40-02, 757-200CB SRM 51-40-02 and
757-200PF SRM 51-40-02, then a fastener of the same specification, or an approved
substitute, with a length which meets the installation standards in 757-200 SRM
51-40-03, 757-200CB SRM 51-40-03 and 757-200PF SRM 51-40-03 may be used.
7. A Detailed Inspection is defined as: An intensive examination of a specific item,
installation, or assembly to detect damage, failure, or irregularity. Available lighting
is normally supplemented with a direct source of good lighting at an intensity deemed
appropriate. Inspection aids such as mirrors, magnifying lenses, etc. may be
necessary. Surface cleaning and elaborate access procedures may be required.
8. A General Visual Inspection is defined as: A visual examination of an interior or
exterior area, installation or assembly to detect obvious damage, failure or irregularity.
This level of inspection is made from within touching distance unless otherwise
specified. A mirror may be necessary to enhance visual access to all exposed surfaces
in the inspection area. This level of inspection is made under normally available
lighting conditions such as daylight, hangar lighting, flashlight or drop-light and may
require removal or opening of access panels or doors. Stands, ladders or platforms
may be required to gain proximity to the area being checked.
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.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
21 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 22

B. WORK INSTRUCTIONS
PART 1 - AIRPLANES THAT HAVE NOT INCORPORATED THE ORIGINAL ISSUE OF THIS SERVICE
BULLETIN.
WARNING: DO THE DEACTIVATION PROCEDURE FOR THE SPOILERS OR MOVE ALL PERSONS
AND EQUIPMENT AWAY FROM THE SPOILERS. THE SPOILERS CAN RETRACT
QUICKLY AND CAUSE INJURY TO PERSONS OR DAMAGE TO EQUIPMENT.
WARNING: IF THE EXTERNAL POWER SUPPLY HAS AN EARTH GROUNDED NEUTRAL, THERE
MUST NOT BE AN OPEN OR FLOATING GROUND IN THE NEUTRAL CIRCUIT WIRING
OF THE SUPPLY OR THE AIRPLANE. IF AN OPEN OR FLOATING GROUND IS
PRESENT, THE AIRPLANE CAN BE PUT AT AN ELECTRICAL POTENTIAL ABOVE
EARTH GROUND. THIS ELECTRICAL POTENTIAL CAN RESULT IN ELECTRIC SHOCK
WITH POSSIBLE SEVERE INJURY TO PERSONNEL WHO TOUCH THE AIRPLANE.
WARNING: REMOVE THE ELECTRICAL POWER FROM THE EXTERNAL POWER CABLE BEFORE
YOU CONNECT THE CABLE TO THE AIRPLANE. INJURY TO PERSONS CAN BE
CAUSED BY AN ELECTRICAL SHOCK.
1. Remove electrical power from the airplane and attach a DO-NOT-CLOSE tag to each opened
circuit breaker. Refer to 757 AMM 24-22-00 as an accepted procedure.
2. Disconnect the battery connectors from the batteries. Refer to 757 AMM 24-31-01 (for main battery)
and 757 AMM 24-31-03 (for auxiliary power unit (APU) battery) as accepted procedures.
3. Put each of the following fuel pump and valve control switches in the position shown below.
PositionLocationSwitch
OFFP5 PanelL FWD PUMP
OFFP5 PanelLEFT C PUMP
OFFP5 PanelR AFT PUMP
OFFP5 PanelRIGHT C PUMP
OFFP5 PanelR FWD PUMP
OFFP5 PanelL AFT PUMP
CUTOFFP10 StandL FUEL CONTROL
CUTOFFP10 StandR FUEL CONTROL
NORMALP8 StandL FIRE HANDLE
NORMALP8 StandR FIRE HANDLE
NORMALP8 StandAPU FIRE SWITCH
4. Open these circuit breakers. Attach a DO-NOT-CLOSE tag to each opened circuit breaker:
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
22 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 23

Circuit BreakerNamePanel / Location
C369L FUEL OVRD PUMPP6-3 / F14
C370R FUEL OVRD PUMPP6-4 / F20
C366L AFT FUEL BOOST PUMPP6-3 / H14
C368R FWD FUEL BOOST PUMPP6-3 / H17
C371R AFT FUEL BOOST PUMPP6-4 / H20
C372L FWD FUEL BOOST PUMPP6-4 / H23
5. Replace the control relays in the P33 panel for the fuel boost pumps in accordance with FIGURE
1 and FIGURE 3.
6. Replace the control relays in the P37 panel for the fuel boost pumps in accordance with FIGURE
2 and FIGURE 3.
7. Measure the electrical bonding resistance between each GFI Relay K187, K10011, K190 and P33
Panel, Plate C in accordance with FIGURE 4.
8. Measure the electrical bonding resistance between each GFI Relay K188, K189, K10012 and P37
Panel, Plate B in accordance with FIGURE 5.
9. Remove the DO-NOT-CLOSE tags and close these circuit breakers:
Circuit BreakerNamePanel / Location
C369L FUEL OVRD PUMPP6-3 / F14
C370R FUEL OVRD PUMPP6-4 / F20
C366L AFT FUEL BOOST PUMPP6-3 / H14
C368R FWD FUEL BOOST PUMPP6-3 / H17
C371R AFT FUEL BOOST PUMPP6-4 / H20
C372L FWD FUEL BOOST PUMPP6-4 / H23
10. Restore electrical power to the airplane. Refer to 757 AMM 24-22-00 as an accepted procedure.
11. Connect the battery connectors to the batteries. Refer to 757 AMM 24-31-01 (for main battery)
and 757 AMM 24-31-03 (for auxiliary power unit (APU) battery) as accepted procedures.
12. Prepare to do the following operational test of the GFI relay installation:
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
23 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 24

a. Make sure that the center fuel tank contains a fuel quantity between 7,000 and 15,000 pounds
(3,200 and 6,800 kilograms).
b. Make sure that the left main fuel tank contains a fuel quantity between 3,000 and 5,000 pounds
(1,400 and 2,300 kilograms).
c. Make sure that the right main fuel tank contains a fuel quantity between 3,000 and 5,000
pounds (1,400 and 2,300 kilograms).
d. Make sure the following valves are closed. Refer to 757 AMM 28-22-03 or approved equivalent
procedure:
LocationValve
Rear Spar at LH IRSS 264.50Engine Fuel Shutoff Valve (Spar
Valve) for the No. 1 Tank
Rear Spar at RH IRSS 264.50Engine Fuel Shutoff Valve (Spar
Valve) for the No. 2 Tank
Rear Spar at LBL 13.70, WL 184.35The Crossfeed Valve(s)
LH and RH Rear Spars at IRSS 206.75The Defuel Valve
WARNING: DO NOT OPERATE A FUEL PUMP IF THE LOW PRESSURE LIGHT COMES ON
AND STAYS ON. FUEL VAPORS IN THE TANK MAY IGNITE AND CAUSE A FIRE
OR EXPLOSION.
e. To operate any of the fuel pumps, personnel must be in the flight compartment to monitor the
fuel quantity and the low pressure indication in the fuel tank. Immediately set the applicable
fuel pump switch to OFF if the PRESS light comes on and stays on.
f. Open the fueling station door, 621GB. Refer to 757 AMM 06-44-00 as an accepted procedure.
g. Do a test of the left aft fuel boost pump control relay (K187) located in the P33 panel as shown
below.
Left Aft Fuel Boost Pump Control Relay - Operation
(1) Push the left aft fuel boost pump (L AFT PUMP) switch-light on the P5-2 fuel management
control panel to the ON position.
(2) Listen and make sure the left aft fuel boost pump operates.
(3) Make sure the left aft fuel boost pump PRESS light on the P5-2 fuel management control
panel goes off.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
24 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 25

CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE LEFT
AFT FUEL BOOST PUMP (L AFT PUMP) SWITCH-LIGHT TO THE OFF
POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(4) Push the left aft fuel boost pump (L AFT PUMP) switch-light to the OFF position.
(5) Listen and make sure the left aft fuel boost pump does not operate.
(6) Make sure the left aft fuel boost pump PRESS light comes on.
Left Aft Fuel Boost Pump - Ground Fault Interruption Function
(1) Push the left aft fuel boost pump (L AFT PUMP) switch-light on the P5-2 fuel management
control panel to the ON position.
(2) Listen and make sure the left aft fuel boost pump operates.
(3) Make sure the left aft fuel boost pump PRESS light on the P5-2 fuel management control
panel goes off.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE LEFT
AFT FUEL BOOST PUMP (L AFT PUMP) SWITCH-LIGHT TO THE OFF
POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(4) Push the left aft fuel boost pump GFI control relay K187 TEST button.
(5) Listen and make sure the left aft fuel boost pump does not operate.
(6) Make sure the left aft fuel boost pump PRESS light comes on.
(7) Make sure the left aft fuel boost pump GFI control relay K187 RESET button has moved
up so that a white band is visible.
NOTE: The RESET button located at the top edge of GFI relay (K187) moves up, to
expose a narrow, white band when the GFI circuit turns off the K187 relay due
to a ground fault, or results when you push the TEST button located on the top
surface of the K187 relay.
(8) Push the left aft fuel boost pump (L AFT PUMP) switch-light to the OFF position.
(9) Push in the left aft fuel boost pump GFI control relay K187 RESET button. Make sure the
RESET button does not move up and the white band is not visible.
(10) Push the left aft fuel boost pump (L AFT PUMP) switch-light on the P5-2 fuel management
control panel to the ON position.
(11) Listen and make sure the left aft fuel boost pump operates.
(12) Make sure the left aft fuel boost pump PRESS light on the P5-2 fuel management control
panel goes off.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
25 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 26

CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE LEFT
AFT FUEL BOOST PUMP (L AFT PUMP) SWITCH-LIGHT TO THE OFF
POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(13) Push the left aft fuel boost pump (L AFT PUMP) switch-light to the OFF position.
(14) Listen and make sure the left aft fuel boost pump does not operate.
(15) Make sure the left aft fuel boost pump PRESS light on the P5-2 fuel management control
panel comes on.
h. Do a test of the left forward fuel boost pump control relay (K188) located in the P37 panel as
shown below.
Left Forward Fuel Boost Pump Control Relay - Operation
(1) Push the left forward fuel boost pump (L FWD PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(2) Listen and make sure the left forward fuel boost pump operates.
(3) Make sure the left forward fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE LEFT
FORWARD FUEL BOOST PUMP (L FWD PUMP) SWITCH-LIGHT TO THE
OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(4) Push the left forward fuel boost pump (L FWD PUMP) switch-light to the OFF position.
(5) Listen and make sure the left forward fuel boost pump does not operate.
(6) Make sure the left forward fuel boost pump PRESS light comes on.
Left Forward Fuel Boost Pump - Ground Fault Interruption Function
(1) Push the left forward fuel boost pump (L FWD PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(2) Listen and make sure the left forward fuel boost pump operates.
(3) Make sure the left forward fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE LEFT
FORWARD FUEL BOOST PUMP (L FWD PUMP) SWITCH-LIGHT TO THE
OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(4) Push in the left forward fuel boost pump GFI control relay K188 TEST button.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
26 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 27

(5) Listen and make sure the left forward fuel boost pump does not operate.
(6) Make sure the left forward fuel boost pump PRESS light comes on.
(7) Make sure the left forward fuel boost pump GFI control relay K188 RESET button has
moved up so that a white band is visible.
NOTE: The RESET button located at the top edge of GFI relay (K188) moves up, to
expose a narrow, white band when the GFI circuit turns off the K188 relay due
to a ground fault, or results when you push the TEST button located on the top
surface of the K188 relay.
(8) Push the left forward fuel boost pump (L FWD PUMP) switch-light to the OFF position.
(9) Push in the left forward fuel boost pump GFI control relay K188 RESET button. Make
sure the RESET button does not move up and the white band is not visible.
(10) Push the left forward fuel boost pump (L FWD PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(11) Listen and make sure the left forward fuel boost pump operates.
(12) Make sure the left forward fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE LEFT
FORWARD FUEL BOOST PUMP (L FWD PUMP) SWITCH-LIGHT TO THE
OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(13) Push the left forward fuel boost pump (L FWD PUMP) switch-light to the OFF position.
(14) Listen and make sure the left forward fuel boost pump does not operate.
(15) Make sure the left forward fuel boost pump PRESS light on the P5-2 fuel management
control panel comes on.
i. Do a test of the left override fuel boost pump control relay (K10011) located in the P33 panel
as shown below.
Left Override Fuel Boost Pump Control Relay - Operation
(1) Push the left override fuel boost pump (LEFT C PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(2) Listen and make sure the left override fuel boost pump operates.
(3) Make sure the left override fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
27 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 28

NOTE: Low pressure (PRESS) light comes on momentarily after the pump switch is set
to the ON position.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE LEFT
OVERRIDE FUEL BOOST PUMP (LEFT C PUMP) SWITCH-LIGHT TO THE
OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(4) Push the left override fuel boost pump (LEFT C PUMP) switch-light to the OFF position.
(5) Listen and make sure the left override fuel boost pump does not operate.
NOTE: The left override fuel boost pump PRESS light stays off when the pump switch
is turned to OFF.
Left Override Fuel Boost Pump - Ground Fault Interruption Function
(1) Push the left override fuel boost pump (LEFT C PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(2) Listen and make sure the left override fuel boost pump operates.
(3) Make sure the left override fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
NOTE: Low pressure (PRESS) light comes on momentarily after the pump switch is set
to the ON position.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE LEFT
OVERRIDE FUEL BOOST PUMP (LEFT C PUMP) SWITCH-LIGHT TO THE
OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(4) Push the left override fuel boost pump GFI control relay K10011 TEST button.
(5) Listen and make sure the left override fuel boost pump does not operate.
(6) Make sure the left override fuel boost pump PRESS light comes on.
(7) Make sure the left override fuel boost pump GFI control relay K10011 RESET button has
moved up so that a white band is visible.
NOTE: The RESET button located at the top edge of GFI relay (K10011) moves up, to
expose a narrow, white band when the GFI circuit turns off the K10011 relay
due to a ground fault, or results when you push the TEST button located on the
top surface of the K10011 relay.
(8) Push the left override fuel boost pump (LEFT C PUMP) switch-light to the OFF position.
(9) Make sure the left override fuel boost pump PRESS light goes OFF.
(10) Push in the left override fuel boost pump GFI control relay K10011 RESET button. Make
sure the RESET button does not move up and the white band is not visible.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
28 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 29

(11) Push the left override fuel boost pump (LEFT C PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(12) Listen and make sure the left override fuel boost pump operates.
(13) Make sure the left override fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE LEFT
OVERRIDE FUEL BOOST PUMP (LEFT C PUMP) SWITCH-LIGHT TO THE
OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(14) Push the left override fuel boost pump switch-light to the OFF position.
(15) Listen and make sure the left override fuel boost pump does not operate.
NOTE: The left override fuel boost pump PRESS light stays off when the pump switch
is turned to OFF.
j. Do a test of the right aft fuel boost pump control relay (K189) located in the P37 panel as
shown below.
Right Aft Fuel Boost Pump Control Relay - Operation
(1) Push the right aft fuel boost pump (R AFT PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(2) Listen and make sure the right aft fuel boost pump operates.
(3) Make sure the right aft fuel boost pump PRESS light on the P5-2 fuel management control
panel goes off.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE
RIGHT AFT FUEL BOOST PUMP (R AFT PUMP) SWITCH-LIGHT TO THE
OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(4) Push the right aft fuel boost pump (R AFT PUMP) switch-light to the OFF position.
(5) Listen and make sure the right aft fuel boost pump does not operate.
(6) Make sure the right aft fuel boost pump PRESS light comes on.
Right Aft Fuel Boost Pump - Ground Fault Interruption Function
(1) Push the right aft fuel boost pump (R AFT PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(2) Listen and make sure the right aft fuel boost pump operates.
(3) Make sure the right aft fuel boost pump PRESS light on the P5-2 fuel management control
panel goes off.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
29 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 30

CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE
RIGHT AFT FUEL BOOST PUMP (R AFT PUMP) SWITCH-LIGHT TO THE
OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(4) Push the right aft fuel boost pump GFI control relay K189 TEST button.
(5) Listen and make sure the right aft fuel boost pump does not operate.
(6) Make sure the right aft fuel boost pump PRESS light comes on.
(7) Make sure the right aft fuel boost pump GFI control relay K189 RESET button has moved
up so that a white band is visible.
NOTE: The RESET button located at the top edge of GFI relay (K189) moves up, to
expose a narrow, white band when the GFI circuit turns off the K189 relay due
to a ground fault, or results when you push the TEST button located on the top
surface of the K189 relay.
(8) Push the right aft fuel boost pump (R AFT PUMP) switch-light to the OFF position.
(9) Push in the right aft fuel boost pump GFI control relay K189 RESET button. Make sure
the RESET button does not move up and the white band is not visible.
(10) Push the right aft fuel boost pump (R AFT PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(11) Listen and make sure the right aft fuel boost pump operates.
(12) Make sure the right aft fuel boost pump PRESS light on the P5-2 fuel management control
panel goes off.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE
RIGHT AFT FUEL BOOST PUMP (R AFT PUMP) SWITCH-LIGHT TO THE
OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP (1)
ABOVE.
(13) Push the right aft fuel boost pump (R AFT PUMP) switch-light to the OFF position.
(14) Listen and make sure the right fuel boost pump does not operate.
(15) Make sure the right aft fuel boost pump PRESS light on the P5-2 fuel management control
panel comes on.
k. Do a test of the right forward fuel boost pump control relay (K190) located in the P33 panel
as shown below.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
30 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 31

Right Forward Fuel Boost Pump Control Relay - Operation
(1) Push the right forward fuel boost pump (R FWD PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(2) Listen and make sure the right forward fuel boost pump operates.
(3) Make sure the right forward fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE
RIGHT FORWARD FUEL BOOST PUMP (R FWD PUMP) SWITCH-LIGHT TO
THE OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP
(1) ABOVE.
(4) Push the right forward fuel boost pump (R FWD PUMP) switch-light to the OFF position.
(5) Listen and make sure the right forward fuel boost pump does not operate.
(6) Make sure the right forward fuel boost pump PRESS light comes on.
Right Forward Fuel Boost Pump - Ground Fault Interruption Function
(1) Push the right forward fuel boost pump (R FWD PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(2) Listen and make sure the right forward fuel boost pump operates.
(3) Make sure the right forward fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE
RIGHT FORWARD FUEL BOOST PUMP (R FWD PUMP) SWITCH-LIGHT TO
THE OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP
(1) ABOVE.
(4) Push the right forward fuel boost pump GFI control relay K190 TEST button.
(5) Listen and make sure the right forward fuel boost pump does not operate.
(6) Make sure the right forward fuel boost pump PRESS light comes on.
(7) Make sure the right forward fuel boost pump GFI control relay K190 RESET button has
moved up so that a white band is visible.
NOTE: The RESET button located at the top edge of GFI relay (K190) moves up, to
expose a narrow, white band when the GFI circuit turns off the K190 relay due
to a ground fault, or results when you push the TEST button located on the top
surface of the K190 relay.
(8) Push the right forward fuel boost pump (R FWD PUMP) switch-light to the OFF position.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
31 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 32

(9) Push in the right forward fuel boost pump GFI control relay K190 RESET button. Make
sure the RESET button does not move up and the white band is not visible.
(10) Push the right forward fuel boost pump (R FWD PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(11) Listen and make sure the right forward fuel boost pump operates.
(12) Make sure the right forward fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE
RIGHT FORWARD FUEL BOOST PUMP (R FWD PUMP) SWITCH-LIGHT TO
THE OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM STEP
(1) ABOVE.
(13) Push the right forward fuel boost pump (R FWD PUMP) switch-light to the OFF position.
(14) Listen and make sure the right forward fuel boost pump does not operate.
(15) Make sure the right forward fuel boost pump PRESS light on the P5-2 fuel management
control panel comes on.
l. Do a test of the right override fuel boost pump control relay (K10012) located in the P37 panel
as shown below.
Right Override Fuel Boost Pump Control Relay - Operation
(1) Push the right override fuel boost pump (RIGHT C PUMP) switch-light on the P5-2 fuel
management control panel at the P5 overhead panel to the ON position.
(2) Listen and make sure the right override fuel boost pump operates.
(3) Make sure the right override fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
NOTE: Low pressure (PRESS) light comes on momentarily after the pump switch is set
to the ON position.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE
RIGHT OVERRIDE FUEL BOOST PUMP (RIGHT C PUMP) SWITCH-LIGHT
TO THE OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM
STEP (1) ABOVE.
(4) Push the right override fuel boost pump (RIGHT C PUMP) switch-light to the OFF position.
(5) Listen and make sure the right override fuel boost pump does not operate.
NOTE: The left override fuel boost pump PRESS light stays off when the pump switch
is turned to OFF.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
32 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 33

Right Override Fuel Boost Pump - Ground Fault Interruption Function
(1) Push the right override fuel boost pump (RIGHT C PUMP) switch-light on the P5-2 fuel
management control panel to the ON position.
(2) Listen and make sure the right override fuel boost pump operates.
(3) Make sure the right override fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
NOTE: Low pressure (PRESS) light comes on momentarily after the pump switch is set
to the ON position.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE
RIGHT OVERRIDE FUEL BOOST PUMP (RIGHT C PUMP) SWITCH-LIGHT
TO THE OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM
STEP (1) ABOVE.
(4) Push the right override fuel boost pump control GFI relay K10012 TEST button.
(5) Listen and make sure the right override fuel boost pump does not operate.
(6) Make sure the right override fuel boost pump PRESS light comes on.
(7) Make sure the right override fuel boost pump GFI control relay K10012 RESET button
has moved up so that a white band is visible.
NOTE: The RESET button located at the top edge of GFI relay (K10012) moves up, to
expose a narrow, white band when the GFI circuit turns off the K10012 relay
due to a ground fault, or results when you push the TEST button located on the
top surface of the K10012 relay.
(8) Push the right override fuel boost pump switch-light to the OFF position.
(9) Make sure the right override fuel boost pump PRESS light goes OFF.
(10) Push the right override fuel boost pump GFI control relay K10012 RESET button in. Make
sure the RESET button does not move up and the white band is not visible.
(11) Push the right override fuel boost pump (RIGHT C PUMP) switch-light on the P5-2 fuel
management control panel to the ON position,
(12) Listen and make sure the right override fuel boost pump operates.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
33 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 34

(13) Make sure the right override fuel boost pump PRESS light on the P5-2 fuel management
control panel goes off.
CAUTION: IF THE AMBER LOW PRESSURE (PRESS) LIGHT STAYS ON, SET THE
RIGHT OVERRIDE FUEL BOOST PUMP (RIGHT C PUMP) SWITCH-LIGHT
TO THE OFF POSITION. FIND THE CAUSE, THEN RESTART TEST FROM
STEP (1) ABOVE.
(14) Push the right override fuel boost pump (RIGHT C PUMP) switch-light to the OFF position.
(15) Listen and make sure the right override fuel boost pump does not operate.
NOTE: The right override fuel boost pump PRESS light stays off when the pump switch
is turned to OFF.
m. Do the following tests of the fuel boost pumps to make sure there is sufficient fuel pump
pressure.
NOTE: If the relay installation was not correct, the pumps operate but may not give sufficient
pressure. The test steps below make sure that the operation of the pumps is correct.
Operation of the Left Fuel Override Pump - Transfer Fuel from Center Tank to Left Main
Tank
(1) Record the fuel quantity for the left, center, and right tanks. (Quantity 1)
(2) Do the setup to transfer fuel from the center tank to the left main tank with the left fuel
override pump. Refer to 757 AMM 28-26-00 as an accepted procedure.
(3) Turn the left fuel override pump (LEFT C PUMP) switch on the P5-2 fuel management
control panel to ON for a period of two minutes.
(4) Turn the left fuel override pump (LEFT C PUMP) switch on the P5-2 fuel management
control panel to OFF after two minutes.
(5) Record the fuel quantity for the left, center, and right tanks. (Quantity 2)
(6) Calculate the amount of fuel that was transferred from the center tank to the left main
tank: Left Tank Quantity 2 - Left Tank Quantity 1 = Fuel Transferred Left Center Tank
Quantity 1 - Center Tank Quantity 2 = Fuel Transferred Center
(7) Make sure Fuel Transferred Left is more than or equal to 400 pounds (200 kilograms). If
the Fuel Transferred Left is less than 400 pounds, check the phase relationship of the
wiring at the K10011 relay.
(8) Make sure Fuel Transferred Center is more than 400 pounds. If the Fuel Transferred
Center is less than 400 pounds (200 kilograms), check the phase relationship of the wiring
at the K10011 relay.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
34 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 35

Operation of the Left Aft Fuel Boost Pump - Transfer Fuel from the Left Main (Aft) Tank
to Center Tank
(1) Do the setup to transfer fuel from the left main tank to the center tank with the left aft fuel
boost pump. Refer to 757 AMM 28-26-00 as an accepted procedure.
(2) Turn the left aft fuel boost pump (L AFT PUMP) switch on the P5-2 fuel management
control panel to ON for a period of two minutes.
(3) Turn the left aft fuel boost pump (L AFT PUMP) switch on the P5-2 fuel management
control panel to OFF after two minutes.
(4) Record the fuel quantity for the left, center, and right tanks. (Quantity 3)
(5) Calculate the amount of fuel that was transferred from the left main tank to the center
tank: Center Tank Quantity 3 - Center Tank Quantity 2 = Fuel Transferred Center Left
Tank Quantity 2 - Left Tank Quantity 3 = Fuel Transferred Left
(6) Make sure Fuel Transferred Center is more than or equal to 200 pounds (100 kilograms).
If the Fuel Transferred Center is less than 200 pounds (100 kilograms), check the phase
relationship of the wiring at the K187 relay.
(7) Make sure Fuel Transferred Left is more than or equal to 200 pounds (100 kilograms). If
the Fuel Transferred Left is less than 200 pounds (100 kilograms), check the phase
relationship of the wiring at the K187 relay.
Operation of the Left Forward Fuel Boost Pump - Left Main (Forward) Tank to Center
Tank
(1) Do the setup to transfer fuel from the left main tank to the center tank with the left forward
fuel boost pump. Refer to 757 AMM 28-26-00 as an accepted procedure.
(2) Turn the left forward fuel boost pump (L FWD PUMP) on the P5-2 fuel management
control panel to ON for a period of two minutes.
(3) Turn the left forward fuel boost pump (L FWD PUMP) on the P5-2 fuel management
control panel to OFF after two minutes.
(4) Record the fuel quantity for the left, center, and right tanks. (Quantity 4)
(5) Calculate the amount of fuel that was transferred from the left main tank to the center
tank: Center Tank Quantity 4 - Center Tank Quantity 3 = Fuel Transferred Center Left
Tank Quantity 3 - Left Tank Quantity 4 = Fuel Transferred Left
(6) Make sure Fuel Transferred Center is more than or equal to 200 pounds (100 kilograms).
If the Fuel Transferred Center is less than 200 pounds (100 kilograms) check the phase
relationship of the wiring at the K188 relay.
(7) Make sure Fuel Transferred Left is more than 200 pounds (100 kilograms). If the Fuel
Transferred Left is less than 200 pounds, check the phase relationship of the wiring at
the K188 relay.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
35 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 36

Operation of the Right Override Fuel Boost Pump - Center Tank to Right Main Tank
(1) Do the setup to transfer fuel from the center tank to the right main tank with the right
override fuel boost pump. Refer to 757 AMM 28-26-00 as an accepted procedure.
(2) Turn the right override fuel boost pump (RIGHT C PUMP) switch on the P5-2 fuel
management control panel to ON for a period of two minutes.
(3) Turn the right override fuel boost pump (RIGHT C PUMP) switch on the P5-2 fuel
management control panel to OFF after two minutes.
(4) Record the fuel quantity for the left, center, and right tanks. (Quantity 5)
(5) Calculate the amount of fuel that was transferred from the center tank to the right main
tank: Right Tank Quantity 5 - Right Tank Quantity 4 = Fuel Transferred Right Center Tank
Quantity 4 - Center Tank Quantity 5 = Fuel Transferred Center
(6) Make sure Fuel Transferred Right is more than or equal to 400 pounds (200 kilograms).
If the Fuel Transferred Right is less than 400 pounds (200 kilograms), check the phase
relationship of the wiring at the K10012 relay.
(7) Make sure Fuel Transferred Center is more than or equal to 400 pounds (200 kilograms).
If the Fuel Transferred Center is less than 400 pounds (200 kilograms), check the phase
relationship of the wiring at the K10012 relay.
Operation of the Right Aft Fuel Boost Pump - Right Main (Aft) Tank to Center Tank
(1) Do the setup to transfer fuel from the right main tank to the center tank with the right aft
fuel boost pump.
(2) Turn the right aft fuel boost pump (R AFT PUMP) switch on the P5-2 fuel management
control panel to ON for a period of two minutes.
(3) Turn the right aft fuel boost pump (R AFT PUMP) switch on the P5-2 fuel management
control panel to OFF after two minutes.
(4) Record the fuel quantity for the left, center, and right tanks. (Quantity 6)
(5) Calculate the amount of fuel that was transferred from the right main tank to the center
tank: Center Tank Quantity 6 - Center Tank Quantity 5 = Fuel Transferred Center Right
Tank Quantity 5 - Right Tank Quantity 6 = Fuel Transferred Right
(6) Make sure Fuel Transferred Center is more than or equal to 200 pounds (100 kilograms).
If the Fuel Transferred Center is less than 200 pounds (100 kilograms), check the phase
relationship of the wiring at the K189 relay.
(7) Make sure Fuel Transferred Right is more than 200 pounds (100 kilograms). If the Fuel
Transferred Right is less than 200 pounds (100 kilograms), check the phase relationship
of the wiring at the K189 relay.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
36 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 37

Operation of the Right Forward Fuel Boost Pump - Right Main (Forward) Tank to Center
Tank
(1) Do the setup to transfer fuel from the right main tank to the center tank with the right
forward fuel boost pump. Refer to 757 AMM 28-26-00 as an accepted procedure.
(2) Turn the right forward fuel boost pump (R FWD PUMP) switch on the P5-2 fuel
management control panel to ON for a period of two minutes.
(3) Turn the right forward fuel boost pump (R FWD PUMP) switch on the P5-2 fuel
management control panel to OFF after two minutes.
(4) Record the fuel quantity for the left, center, and right tanks. (Quantity 7)
(5) Calculate the amount of fuel that was transferred from the right main tank to the center
tank: Center Tank Quantity 7 - Center Tank Quantity 6 = Fuel Transferred Center Right
Tank Quantity 6 - Right Tank Quantity 7 = Fuel Transferred Right
(6) Make sure Fuel Transferred Center is more than or equal to 200 pounds (100 kilograms).
If the Fuel Transferred Center is less than 200 pounds (100 kilograms), check the phase
relationship of the wiring at the K190 relay.
(7) Make sure Fuel Transferred Right is more than 200 pounds or equal to (100 kilograms).
If the Fuel Transferred Right is less than 200 pounds (100 kilograms), check the phase
relationship of the wiring at the K190 relay.
13. Put the airplane back to a serviceable condition.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
37 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 38

PART 2 - AIRPLANES THAT HAVE PREVIOUSLY INCORPORATED THE ORIGINAL ISSUE OF
THIS SERVICE BULLETIN.
1. Do a General Visual Inspection of the Installation screws for the GFI relays K187, K10011, K190,
on the P33 Panel, Plate C, to determine that each installation screw has enough grip length to
hold the screws in each nutplate. The chamfer on the shaft of the screw should be fully visible,
not to exceed (3) three full threads. Refer to 757-200 SRM 51-40-05 , 757-200CB SRM 51-40-05,
757-200PF SRM 51-40-05 and BAC5009 as accepted procedures. If any of the mounting screws
cannot be verified by sight or with the aid of mirrors remove the mounting screws (4), (one at each
corner) on plate C of the P33 Panel, and move the plate C to get access to inspect the GFI Relay
mounting screws. Re-install the mounting screws for the Plate C.
2. Do a General Visual Inspection of the Installation screws for the GFI relays K188, K189, K10012,
on the P37 Panel, Plate B, to determine that each installation screw has enough grip length to
hold the screws in each nutplate. The chamfer on the shaft of the screw should be fully visible,
not to exceed (3) three full threads. Refer to 757-200 SRM 51-40-05 , 757-200CB SRM 51-40-05,
757-200PF SRM 51-40-05 and BAC5009 as accepted procedures. If any of the mounting screws
cannot be verified by sight or with the aid of mirrors remove the top mounting screws (opposite
the hinge on Plate B, P37 Panel) and pull the Plate B to get access to inspect the GFI Relay
mounting screws. Re-install the mounting screws for the Plate B.
3. Measure the electrical bonding resistance between each GFI Relay K187, K10011, K190 and P33
Panel, Plate C in accordance with FIGURE 4.
4. Measure the electrical bonding resistance between each GFI Relay K188, K189, K10012 and P37
Panel, Plate B in accordance with FIGURE 5.
5. Put the airplane back to a serviceable condition.
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1: August 24, 2010
38 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 39

The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
12NAS1801-08-7ScrewRemove / Keep1
3MS27418-2ARelayRemove
FIGURE 1: P33 PANEL PLATE 'C' - RELAY REPLACEMENT
(SHEET 1 OF 2)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1 August 24, 2010
39 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 40

MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(b)39324-10676RelayInstall (New)2
Make sure kept
screw grip length is
the correct length
before re-installing.
Refer to 757-200
SRM 51-40-05 ,
757-200CB SRM 51-
40-05, 757-200PF
SRM 51-40-05 and
BAC5009 as accept-
ed procedures.
12NAS1801-08-7ScrewInstall (Kept)
(a)-P33-00P33 PanelIdentify3
(a) Identify on the P33 Panel that this change was done. Refer to SWPM 20-50-10 as an accepted procedure.
(b) Solvent clean the GFI Relay mounting flanges and the Plate C, P33 Panel. Refer to SOPM 20-11-03,
CM3 as an accepted procedure.
FIGURE 1: P33 PANEL PLATE 'C' - RELAY REPLACEMENT
(SHEET 2 OF 2)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1 August 24, 2010
40 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 41

The step numbers shown below agree with the numbers shown in the circle symbols in the figure.
MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
12NAS602-7P  (OR
NAS1801-08-7 option-
al)
ScrewRemove / Keep1
3MS27418-2ARelayRemove
FIGURE 2: P37 PANEL PLATE 'B' - RELAY REPLACEMENT
(SHEET 1 OF 2)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1 August 24, 2010
41 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 42

MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(b)39324-10676RelayInstall (New)2
Make sure kept
screw grip length is
the correct length
before re-installing.
Refer to 757-200
SRM 51-40-05 ,
757-200CB SRM 51-
40-05, 757-200PF
SRM 51-40-05 and
BAC5009 as accept-
ed procedures.
12NAS602-7P  (OR
NAS1801-08-7 option-
al)
ScrewInstall (Kept)
(a)-P33-00P33 PanelIdentify3
(a) Identify on the P33 Panel that this change was done. Refer to SWPM 20-50-10 as an accepted procedure.
(b) Solvent clean the GFI Relay mounting flanges and the Plate C, P33 Panel. Refer to SOPM 20-11-03,CM3
as an accepted procedure.
FIGURE 2: P37 PANEL PLATE 'B' - RELAY REPLACEMENT
(SHEET 2 OF 2)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1 August 24, 2010
42 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 43 (OCR)

BOEING SERVICE BULLETIN 757-28A0078
A2  A2
B2  B2
B1  B1
C2  C2
C1  C1
x1  GFI
FAULT
LOGIC
FUEL BOOST PUMP  FUEL BOOST PUMP
CONTROL RELAY  CONTROL GFI RELAY
BEFORE  AFTER
J30147
FIGURE 3: FUEL BOOST PUMP CONTROL GROUND FAULT INTERRUPTER (GFI) RELAY SCHEMATIC
REFERENCE
(SHEET 1 OF 1)
Original Issue: July 16, 2008
Revision 1 August 24, 2010  BOEING PROPRIETARY -  757-28A0078
Copyright © Unpublished Work - See page 1 for details.  43 of 47

### Page 44

MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(a), (b), (c)-K187GFI RELAYMeasure1
(a), (b), (c)-K10011GFI RELAYMeasure2
(a), (b), (c)-K190GFI RELAYMeasure3
(a) Measure the electrical bonding resistance from the GFI Relay mounting flange to P33, Plate C. Make
sure the resistance measures 0.0025 Ohms (2.5 Milliohms) or less.
(b) If the electrical bonding resistance between the GFI Relay and P33 Panel, Plate C is greater than 0.0025
Ohms(2.5 milliohms) remove the GFI Relay, solvent clean the mounting flange, solvent clean the Plate
FIGURE 4: ELECTRICAL BONDING RESISTANCE CHECK FOR GROUND FAULT INTERRUPTER (GFI)
RELAYS, P33 PANEL
(SHEET 1 OF 2)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1 August 24, 2010
44 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 45

MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
C and screw. Refer to SWPM 20-20-00 as an accepted procedure. Refer to SOPM 20-11-03, CM3 as an
accepted procedure for solvent cleaning.
(c) Select a recommended bonding meter. Refer to as SWPM 20-20-00 an accepted procedure.
FIGURE 4: ELECTRICAL BONDING RESISTANCE CHECK FOR GROUND FAULT INTERRUPTER (GFI)
RELAYS, P33 PANEL
(SHEET 2 OF 2)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1 August 24, 2010
45 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 46

MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
(a), (b), (c)-K188GFI RELAYMeasure1
(a), (b), (c)-K189GFI RELAYMeasure2
(a), (b), (c)-K10012GFI RELAYMeasure3
(a) Measure the electrical bonding resistance from the GFI Relay mounting flange to P37, Plate B. Make
sure the resistance measures 0.0025 Ohms (2.5 Milliohms) or less.
(b) If the electrical bonding resistance between the GFI Relay and P37 Panel, Plate B is greater than 0.0025
Ohms(2.5 milliohms) remove the GFI Relay, solvent clean the mounting flange, solvent clean the Plate
FIGURE 5: ELECTRICAL BONDING RESISTANCE CHECK FOR GROUND FAULT INTERRUPTER (GFI)
RELAYS, P37 PANEL
(SHEET 1 OF 2)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1 August 24, 2010
46 of 47
BOEING SERVICE BULLETIN 757-28A0078

### Page 47

MORE DATAQTYIDENTIFICATIONNAMETASKSTEP
B and screw. Refer to SWPM 20-20-00 as an accepted procedure. Refer to SOPM 20-11-03, CM3 as an
accepted procedure for solvent cleaning.
(c) Select a recommended bonding meter. Refer to as SWPM 20-20-00 an accepted procedure.
FIGURE 5: ELECTRICAL BONDING RESISTANCE CHECK FOR GROUND FAULT INTERRUPTER (GFI)
RELAYS, P37 PANEL
(SHEET 2 OF 2)
BOEING PROPRIETARY -
Copyright © Unpublished Work - See page 1 for details.
Original Issue: July 16, 2008
757-28A0078Revision 1 August 24, 2010
47 of 47
BOEING SERVICE BULLETIN 757-28A0078

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain, except the copies of manufacturers’ service documents, which belong to their rights holders.