Service difficulty report · Unknown · Boeing 737890

Difficulty date
November 26, 2021
Submitted
December 1, 2021
Operation
Air carrier
Aircraft
N584AS
Make and model
Boeing 737890
Aircraft serial
35682
Aircraft time
51,976 hours, 15,412 cycles
Part
Unknown
Part number
UNKNOWN
Condition
Unknown
Location
Unknown
Stage of operation
CR
How discovered
V
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

AT FL370, "SINGLE FMC OPS" ON MCDU SCRATCH PAD. FO ND AMBER "MAP" DISPLAYED. FO PFD, AMBER "LDG ALT" DISPLAYED. NO RNP OR ANP DISPLAYED ON FO ND MCDU POS SHIFT PAGE 3/3 SHOWS NO DATA FOR FMC-R. FOLLOWED QRC FMC FAIL. CONTINUED FLIGHT WITH FMC TRANSFER SWITCH, BOTH ON LEFT. GROUNDED - YES. PERFORMED FMC SYSTEM BITE PER B737-800 FIM 34-61 TASK 801. EACH FLIGHT LEG ON L&R FMC'S INDICATED PROGRAM PIN MISMATCH. AT FMC DIP SWITCH 1, M1990, FOUND SWITCH 1, 3, 5, AND 13 IN THE INCORRECT SETTING FOR YL103 EFFECTIVITY. SET M1990 DIP SWITCHES PER FMC PROGRAM PINS B737-800 WDM 34-61-19 PAGE 13 SHEET 1. FMC SOURCE SELECT SWITCH RETURNED TO NORMAL POSITION.