SDR UALA2008111306499

Service difficulty report · Wire Harness · Boeing 777222

Difficulty date: November 12, 2008
Submitted: December 5, 2008
Operation: Air carrier
Aircraft: N786UA
Make and model: Boeing 777222
Aircraft serial: 26938
Aircraft time: 50,881 hours, 7,544 cycles
Engine: Pwa PW40903
System (JASC): 2497 · Electrical Power System Wiring
Part: Wire Harness
Condition: Faulty
Location: Nr 2 Engine
Stage of operation: IN
How discovered: O
Nature of condition: W
Precautionary procedure: O

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

What was found

NR 2 ENG IDG WILL NOT DISCONNECT. SWAPPED NR 1 AND NR 2 IDG DISCONNECT SWITCH ON OVERHEAD, NO HELP. REMOVED ALL IDG ELECTRICAL CONNECTORS, NO BENT PINS OR DEFECTS NOTED. SUSPECT BAD IDG FROM STOCK. NEW IDG ON ORDER. REPLACED IDG, NO HELP. GCU BITE TEST OK. CHECKED PWR & GND AT CONN DM24001A, CHECKS OK. SOLENOID CHECKS OK. RAN ENG 4 TIMES, GOT IDG TO DISCONNECT ONE TIME. NEED A HEA PAR (PARTIAL) REPLACED IDG, NO HELP. FOUND BAD HARNESS SHORTED TO GROUND. REPLACED HARNESS. IDG DISCONNECT CHECKS GOOD.