Service difficulty report · Hmu · Boeing 737990ER

Difficulty date
April 25, 2022
Submitted
April 28, 2022
Operation
Air carrier
Aircraft
N481AS
Make and model
Boeing 737990ER
Aircraft serial
44106
Aircraft time
24,989 hours, 7,871 cycles
Engine
Cfmint CFM567B27E
Part
Hmu
Part number
1853M56P16
Part serial
BECWD184
Condition
Faulty
Location
#2 Engine
Part time
25,011 hours, 7,875 cycles
Stage of operation
IN
How discovered
V
Nature of condition
O
Precautionary procedure
K

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

WHILE PERFORMING T/C 78273000 FOUND #2 ENGINE SHORT TIME FAULT MSG NUMBER 73-10342 THE FMV POSITION SIGNAL IS OUT OF RANGE. FLIGHT LEG 1 AND 3 DEFERRED PER T/C 78273000. GROUNDED - YES. CONFIRMED FAULT MESSAGE NUMBER 73-10342 STILL ACTIVE ON ENGINE #2. ACCOMPLISHED ACTUATORS TEST REF B737-900 AMM 71-00-00-700-807-F00, ACTUATORS TEST PASSED. CONTINUED WITH B737-900 FIM 73-25 TASK 803, PERFORMED INSPECTION OF RECEPTACLE DP0501 AND RESISTANCE CHECK. FOUND PINS 6 AND 17 DAMAGED, AND RESISTANCE VALUES FROM PINS 35 TO 17 TO BE BELOW RANGE. FOUND NO DAMAGE ON J5 HARNESS OR CONNECTORS, PER STEP F (4)(A) REQUIRES NEW HMU. REMOVED HMU ONLY PER ASA TC N8473000. INSTALLED #2 ENG HMU PER ASA TASK CARD N8473001. NOTE FOR TII REVIEW TASK CARD REVIEW ASA TASK CARD N8473001.