# SDR ASAA2023062443745

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 24, 2023
- Submitted: June 27, 2023
- Operation: Air carrier
- Aircraft: [N467AS](https://openairdocs.org/aircraft/N467AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 36362
- Aircraft time: 33,410 hours, 10,665 cycles
- System (JASC): [7410 · Ignition Power Supply](https://openairdocs.org/jasc/7410)
- Part: Unknown
- Part number: UNKNOWN
- Condition: Unknown
- Location: 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/ASAA2023062443745

## Discrepancy

DURING TASK CARD 78273000 FOUND FAULT CODE 74-30971 THE APL INPUT VOLTAGE FOR THE L EXCITER (IGN 1) IS OUT OF RANGE (LONG TIME). GROUNDED - YES. PERFORMED FIM 74-21 TASK 801. NO FAULTS OR DISCREPANCIES NOTED AS OF THIS TIME DURING TROUBLESHOOTING. PERFORMED IGNITION SYSTEM AUDIBLE TEST REF AMM 74-00-00-750-801-F00. LEFT IGNITER OPERATES NORMAL (AUDIBLE CLICKS) AND NO FAULTS AFTER TEST. ALL DISCRETE SIGNALS ARE NORMAL FOR THE LEFT IGNITION SWITCH. GROUND VERIFICATION SUCCESSFUL.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.