# SDR ASAA2020051732740

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 17, 2020
- Submitted: May 21, 2020
- Operation: Air carrier
- Aircraft: [N487AS](https://openairdocs.org/aircraft/N487AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44108
- Aircraft time: 17,979 hours, 5,611 cycles
- System (JASC): [4970 · APU Indicating System](https://openairdocs.org/jasc/4970)
- Part: Warning System
- Condition: False Activation
- Location: Apu
- Stage of operation: CR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020051732740

## Discrepancy

CSS FAILED FL 400 (3 ATTEMPTS), FAULT LIGHT ILLUMINATED. GROUNDED - YES.  FOUND FAULT 49-31016 OVERTEMP SHUTDOWN. IAW FIM TASK 49-30 TASK 803, STARTED APU NO FAULTS NOTED. APU COLD SOAK START ACCOMPLISHED, SUCCESSFUL.

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