Service difficulty report · Hmu · Boeing 737890

Difficulty date
September 1, 2009
Submitted
September 3, 2009
Operation
Air carrier
Aircraft
N564AS
Make and model
Boeing 737890
Aircraft serial
35103
Aircraft time
11,278 hours, 3,585 cycles
Engine
Cfmint CFM567B27
Part
Hmu
Part number
442369
Part serial
BECW5014
Condition
Malfunctioned
Location
Nr 2 Engine
Part time
1,524 hours, 504 cycles
Stage of operation
TX
How discovered
O
Nature of condition
J
Precautionary procedure
K

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

What was found

NR 2 ENGINE CONTROL LIGHT ILLUMINATED ON TAXI OUT. CHECKED FAULT HISTORY AND FOUND FAULT CODES 75 20582 (TBV DEMAND AND POS SIGNAL DISAGREE) AND 75 20532 (LPTACC DEMAND AND POSITION SIGNALS DISAGREE). ACCOMPLISHED FIM TASK 75 22 00 810 801 F00 (FOR 75 20532) STEP F FOR WIRING CHECK AND FOUND NO DEFECTS. ACCOMPLISHED FIM TASK 75 23 00 810 801 F00 (FOR 75 20582) STEP F FOR WIRING CHECKS AND FOUND NO DEFECTS. PERFORMED TEST 12 (ACTUATORS TEST) PER AMM 71 00 00 700 807 F00. TEST PASSED. ACCOMPLISHED REMOVAL AND REPLACEMENT OF HMU PER ASA AMM 73 21 10 000 801 F00 AND 73 21 10 400 801 F00 STEPS (A) THRU (G). PERFORMED IDLE POWER LEAK CHECK AND NO LEAKS NOTED PER MM 71 00 00 700 801 F00 STEP D F PERFORMED BITE TEST AND TEST GOOD PER MM 71 00 00 700 808 F00.