Service difficulty report · Transmitter · Boeing 737990ER

Difficulty date
August 7, 2015
Submitted
August 12, 2015
Operation
Air carrier
Aircraft
N478AS
Make and model
Boeing 737990ER
Aircraft serial
44105
Aircraft time
187 hours, 61 cycles
Engine
Cfmint CFM567B27E
Part
Transmitter
Part number
QA07656ISSP3
Condition
Failed
Location
Nr 1 Engine Oil
Stage of operation
TX
How discovered
O
Nature of condition
N
Precautionary procedure
O

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

What was found

DURING TAXI-IN, NR 1 ENG OIL FILTER BYPASS LIGHT CAME ON & REMAINED ILLUMINATED UNTIL ENGINE SHUTDOWN. ALL ENGINE INDICATIONS WERE NORMAL, ALL QTY INDICATIONS NORMAL. ACFT GROUNDED. IN EVALUATION, FOUND THE OIL FILTER SIGNALS DISAGREE LIGHT ON, CDU INPUT MONITORING, OIL FILTER BYPASS STATUS OPEN, OPEN REF FIM 79-05,TASK 817. ELECTRONIC ENGINE CONTROL BITE FOUND 79-31121, DUAL CHANNEL FAULT. INSPECTED CHIP DETECTORS AND SCAVENGE SCREENS, FOUND NO CONTAMINATION, REF T/C POWER, PL-79E0-06942-1. REPLACED SCAVENGE OIL FILTER, EXAMINED FILTER ELEMENT, NO CONTAMINATION FOUND, REF MM 79-21-06. BY MEASURING THE RESISTANCE BETWEEN PINS 1 TO 2, 2 TO 3 ON SCAVENGE OIL FILTER TRANSMITTER RECEPTACLE FOUND BOTH OPEN REF FIM 79-21, TASK 806. REPLACED SCAVENGE OIL FILTER TRANSMITTER, OPS CHECK NORMAL, NO LEAK AT THIS TIME REF MM 79-21-07.