SDR ASAA2023090444947

Service difficulty report · Fmc · Boeing 737990ER

Difficulty date: September 4, 2023
Submitted: September 6, 2023
Operation: Air carrier
Aircraft: N478AS
Make and model: Boeing 737990ER
Aircraft serial: 44105
Aircraft time: 30,189 hours, 9,499 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Part number: 1762000101
Part serial: 003128
Condition: Faulty
Location: E/E Shelf E5-2
Part time: 58,795 hours, 17,867 cycles
Stage of operation: NR
How discovered: V
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

LEFT FMC INTERMITTENTLY FAILS AND RESTORES ITSELF FROM LANDING UNTIL PARKED AT THE GATE. LASTED APPROXIMATELY 20 MINUTES. AFTER SHUTDOWN LEFT FMC FAILED AND WOULD NOT RESTORE ITSELF. GROUNDED - YES. REMOVED AND REPLACED L/H FMC, PULLED, COLLARED, AND RESET 2 EACH C/B'S, REQUIRED SOFTWARE LOADED/VERIFIED. OPS CHECKED GOODREF AMM 34-61-02.