# SDR ASAA2021020434011

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 4, 2021
- Submitted: February 6, 2021
- Operation: Air carrier
- Aircraft: [N533AS](https://openairdocs.org/aircraft/N533AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35201
- Aircraft time: 37,735 hours, 10,909 cycles
- Engine: Cfmint CFM567B27
- System (JASC): [4960 · APU Controls](https://openairdocs.org/jasc/4960)
- Part: Sensor
- Part number: 38007021
- Part serial: P8069
- Condition: Faulty
- Location: Apu Bay
- Part time: 14,452 hours, 20,906 cycles
- Stage of operation: CR
- 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/ASAA2021020434011

## Discrepancy

APU FAILED START DURING 2 ATTEMPTS AT FL400 AND 1 ATTEMPT AT FL340.  APU FAULT LIGHT ILLUMINATED ON ALL 3 ATTEMPTS.  GROUNDED - YES.  R & R INLET TEMP SENSOR PER B737-800 FIM 49-30 TASK 803.  NO DEFECTS NOTED NO FAULTS CODES.  CLEARS MEL 49-1B C/N 05021533 MEL 49-1B CLEARED, REF DEFECT 60065681 FOR CCS MEL 49-99A.

---
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.