# SDR ASAA2021120836882

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 8, 2021
- Submitted: December 22, 2021
- Operation: Air carrier
- Aircraft: [N407AS](https://openairdocs.org/aircraft/N407AS), registered now
- Make and model: Boeing 737-900ER
- Registry model: [Boeing 737-900ER](https://openairdocs.org/model/boeing-737-900er) (OpenAirDocs)
- Aircraft serial: 41731
- Aircraft time: 34,327 hours, 10,785 cycles
- System (JASC): [7720 · Engine Temperature Indicating System](https://openairdocs.org/jasc/7720)
- Part: Unknown
- Condition: Unknown
- 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/ASAA2021120836882

## Discrepancy

MAINT MSG 77-20861 {BOTTOM LEFT EGT SIGNAL (T495S3) IS OUT OF RANGE - LONG TIME FAULT (450 FLT HRS) DEFERRAL PER T/C 78273000. GROUNDED - YES. FOUND S4 EGT READING TO HAVE DASHES. ACCOMPLISHED T49.5 AND EGT SYSTEM INSPECTION REF B737-900 AMM 77-21-01-200-801-F00.  CONTINUITY CHECKS ARE WITHIN LIMITS FOR ALL HARNESSES AND PROBES.  ACCOMPLISHED EGT CLEANING REF AMM 77-21-00-140-801.  ACCOMPLISHED EEC TEST REF AMM 73-21-00-700-804-F00. NO FAULTS FOUND. GROUND VERIFICATION SUCCESSFUL.

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