# SDR ASAA2016092018093

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 20, 2016
- Submitted: September 26, 2016
- Operation: Air carrier
- Aircraft: [N474AS](https://openairdocs.org/aircraft/N474AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 40715
- Aircraft time: 4,934 hours, 1,616 cycles
- System (JASC): [7722 · Engine EGT/TIT Indicating System](https://openairdocs.org/jasc/7722)
- Part: Probe
- Part number: TC29603
- Condition: Out Of Tolerance
- Location: Nr 2 Engine
- Stage of operation: IN
- How discovered: O
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2016092018093

## Discrepancy

NR 2 ENGINE HAD ECONOMIC FAULT CODE 77-20872, TOP LT EGT SIGNAL OUT OF RANGE.  ACFT GROUNDED.  VERIFIED DISCREPANCY T49.5 INPUT MONITORING PAGE SHOWS S4 SHOWING DASHES. PERFORMED EGT SYSTEM INSPECTION, IAW AMM 77-21-01. FOUND S4 OUT OF TOLERANCE, IAW AMM 77-21-01. S4 T49.5 PROBE REMOVED & REPLACED, IAW AMM 77-21-01, OPS NORMAL. GROUND VERIFICATION CHECKED GOOD.

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