Service difficulty report · Wire · Boeing 737990ER

Difficulty date
December 29, 2022
Submitted
January 3, 2023
Operation
Air carrier
Aircraft
N434AS
Make and model
Boeing 737990ER
Aircraft serial
61620
Aircraft time
24,885 hours, 7,747 cycles
Part
Wire
Condition
Faulted
Location
Window Heat
Stage of operation
CL
How discovered
O
Nature of condition
J
Precautionary procedure
O

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

What was found

AFTER ROTATION, THE MASTER CAUTION AND L SIDE (L20) WINDOW OVERHEAT ILLUMINATED. WE RAN THE QRH AND THE CAUTION EXTINGUISHED. 30 SECS LATER, CAUTION ILLUMINATED AGAIN & TURNED OFF ASSOCIATED WINDOW HEAT SWITCH AS DIRECTED BY QRH & CONTINUED THE FLIGHT. GROUNDED - YES. C/W OPS TEST OF WINDOW HEAT SYSTEM, CHECKS OK. C/W FIM PROCEDURES FOR L2 WINDOW HEAT, BIT VERIFY GREEN LIGHT ILLUM, NO ACTIVE FAULTS. WHC FAULT HISTORY FAULTED WINDOW TEMP SENSOR. WINDOW TEMP SENSOR RESISTANCE CHECKS OK. WIRING CHECK BETWEEN WHC AND L2 WINDOW CHECKS OK. GVI OF L2 COIL WIRE CHECKS OK, AS A PRECAUTION, REPLACED COIL WIRE WITH NEW. WINDOW HEAT OPS CHECKS OK. REF FIM 30-41 TASKS 801 & 811, AMM 30-41-00-200-801 & 30-41-00-710-801.