# SDR ASAA2026051666171

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 16, 2026
- Submitted: May 19, 2026
- Operation: Air carrier
- Aircraft: [N506AS](https://openairdocs.org/aircraft/N506AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35690
- Aircraft time: 63,164 hours, 19,549 cycles
- System (JASC): [2421 · AC Generator-Alternator](https://openairdocs.org/jasc/2421)
- Part: Gcu
- Condition: Faulted
- Location: Zone 100
- Stage of operation: IN
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2026051666171

## Discrepancy

GEN CONTROL UNIT A/C LEFT IN E+E BAY HAS BTB FAULT LIGHT ILLUMINATED. GROUNDED - YES. RESET GCU REF AMM 24-21-81-400-801 NO FAULTS NOTED.

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