# SDR ASAA2021012133936

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 21, 2021
- Submitted: January 26, 2021
- Operation: Air carrier
- Aircraft: [N533AS](https://openairdocs.org/aircraft/N533AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35201
- Aircraft time: 37,654 hours, 10,884 cycles
- System (JASC): [4930 · APU Engine Fuel and Control](https://openairdocs.org/jasc/4930)
- Part: Fault Light
- Condition: False Activation
- Location: Apu
- Stage of operation: CR
- How discovered: O
- Nature of condition: N
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2021012133936

## Discrepancy

FAULT LIGHT ILLUMINATED DURING APU START ATTEMPT AT FL410.  SUCCESSFUL CSS ACCOMPLISHED AT FL330 AFTER FAULT LIGHT EXTINGUISHED.  APU STARTED OK ON GROUND ALSO.  GROUNDED-YES.  ACCOMPLISHED APU BITE, IAW B737-800 FIM 49 33 TASK 803 FAULT CODES 49-31295 AND 49-31016 AND FLIGHT LEGS THREE.  NO CURRENT FAULTS NOTED.  ACCOMPLISHED OPERATIONS CHECK AT APU, IAW B737-800 AMM 49-11-00.  OPERATIONS CHECK OK.

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