# SDR ASAA2023103045855

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 25, 2023
- Submitted: October 30, 2023
- Operation: Air carrier
- Aircraft: [N459AS](https://openairdocs.org/aircraft/N459AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 36352
- Aircraft time: 35,864 hours, 11,244 cycles
- System (JASC): [2410 · Alternator-Generator Drive](https://openairdocs.org/jasc/2410)
- Part: Idg
- Part number: 761574B
- Part serial: AAAH010220
- Condition: Faulted
- Location: #1 Engine
- Part time: 35,913 hours, 11,256 cycles
- Stage of operation: DE
- How discovered: V
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2023103045855

## Discrepancy

#1 GENERATOR CAME OFF LINE DURING DESCENT AND WOULDNT RESET. SOURCE OFF LIGHT GEN OFF. BUS LIGHT. GROUNDED - YES. PERFORMED BITE TEST ON #1 IDG PER FIM 24-21 TASK 801. NO FURTHER FAULTS NOTED. INITIAL EVALUATION REVEALED IDG FAULT LIGHT ON GCU 1. PERFORMED WIRING CHECKS LISTED ON FIM 24-21 TASK 805, NO DISCREPANCIES NOTED. PER FIM 24-21 TASK 805, REPLACED GCU 1 REF AMM 24-21-81/401, OPS CHECK FAILED, SOURCE OFF LIGHT ILLUMINATES FOR #1 GENERATOR. SUSPECT BAD IDG. REMOVED AND REPLACED #1 IDG, REF AMM 24-11-11, LEAK CHECK GOOD, PERFORMED GCU BITE TEST.

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