# SDR ASAA2020040632615

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 3, 2020
- Submitted: April 6, 2020
- Operation: Air carrier
- Aircraft: [N570AS](https://openairdocs.org/aircraft/N570AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35185
- Aircraft time: 49,810 hours, 14,725 cycles
- System (JASC): [2613 · Overheat Detection](https://openairdocs.org/jasc/2613)
- Part: Overheat Sensor
- Part number: 90202001
- Condition: Faulty
- Location: Apu
- Stage of operation: TX
- How discovered: O
- Nature of condition: N
- Precautionary procedure: D
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020040632615

## Discrepancy

APU DET INOP LIGHT ILLUMINATED UPON PUSHBACK. GROUNDED - YES. VERIFIED DISCREP - HARD FAIL. ENG/APU FIRE DET MODULE BITE PER B737-800 FIM 26-10 TASK 802 SHOWS APU TAILPIPE DET AT FAULT. RANG OUT SAME DETECTOR AND READ 160K OHMS - SHOULD BE 4K OHMS. REMOVED/REPLACED TAILPIPE OVHT DET ASSY REF B737-800 AMM 26-15-01. OPS NML REF AMM 26-15-00. GROUND VERIFICATION TEST GOOD.

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