# SDR ASAA2017051120740

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 11, 2017
- Submitted: May 15, 2017
- Operation: Air carrier
- Aircraft: [N512AS](https://openairdocs.org/aircraft/N512AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 39043
- Aircraft time: 33,686 hours, 10,170 cycles
- System (JASC): [7722 · Engine EGT/TIT Indicating System](https://openairdocs.org/jasc/7722)
- Part: Probe
- Part number: TC29604
- Condition: Out Of Limits
- Location: Nr 1 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/ASAA2017051120740

## Discrepancy

DIAGNOSTICS REPORTS NR 1 ENGINE TREND DATA SHOWS A SHIFT IN EGT, HOT DAY MARGIN, ALL OTHER PARAMETERS NORMAL. EGT INDICATION ERRORS ARE SUSPECT PRI: 2 ETOPS SIGNIFICANT SYSTEM. GROUNDED - YES. ACCOMPLISHED T49.5 PROBE & EGT SYSTEM INSPECTION AND CLEANING. FOUND T49.5 S4 PROBE OUT OF TOLERANCE. REPLACED T49.5 S4 PROBE. OPS CK GOOD. REF AMM 77-21-00-140-801, AMM 77-21-01-200-801-F00, AMM 77-21-01/401. BEFORE CLEANING T49.5 SENSOR VALUES: T49.5 S1 59.66, S2 32.59, S3 36.91, S4 92.55. AFTER CLEANING T49.5 SENSOR VALUES: T49.5 S1 16.68, S2 12.72, S3 12.64, S4 25.06.

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