SDR ASAA2017090821893

Service difficulty report · Probe · Boeing 737890

Difficulty date: September 8, 2017
Submitted: September 12, 2017
Operation: Air carrier
Aircraft: N596AS
Make and model: Boeing 737890
Aircraft serial: 35688
Aircraft time: 35,716 hours, 10,865 cycles
System (JASC): 7722 · Engine EGT/TIT Indicating System
Part: Probe
Part number: TC29603
Condition: Out Of Limits
Location: Nr 1 Engine
Stage of operation: IN
How discovered: O
Nature of condition: O
Precautionary procedure: K

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

What was found

WHILE PERFORMING T/C 78273000 NR 1 ENGINE HAS ECONOMIC FAULT MESSAGE 77-20861. "EGT SIGNAL OUT OF RANGE" ECONOMIC FAULT, DEFERRED PER T/C 78273000 NR 1 ENGINE. GROUNDED - YES. VERIFIED THAT THE FAULT WAS STILL ACTIVE. PERFORMED A T49.5 PROBE AND EGT SYSTEM INSPECTION PER AMM 77-21-01-200-801-F00. FOUND S3 PROBE RESISTANCE VALUES OUT OF LIMITS. REPLACED THE S3 T49.5 PROBE PER AMM 77-21-01/401. OPS CHECKS GOOD PER SAME.