# SDR ASAA2019072830232

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 28, 2019
- Submitted: July 30, 2019
- Operation: Air carrier
- Aircraft: [N596AS](https://openairdocs.org/aircraft/N596AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35688
- Aircraft time: 42,759 hours, 12,936 cycles
- System (JASC): [4970 · APU Indicating System](https://openairdocs.org/jasc/4970)
- Part: Sensor
- Part number: MS280341
- Condition: Corroded
- Location: Apu
- Stage of operation: NR
- 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/ASAA2019072830232

## Discrepancy

APU TREND DATA SHOWS CT5ATP TEMP IS AT OR ABOVE THE THRESHOLD 605 DEGREES GROUNDED - YES. NO RECENT RELATED MTX MESSAGES IN APU HISTORY. NO BLOCKAGE IN AIR INLET OR COMPRESSOR INLET PLENUM. REMOVED INLET TEMP SENSOR & FOUND IT TO BE CORRODED & DIRTY. CLEANED CONNECTOR & REPLACED INLET TEMP SENSOR REF AMM 49-61-31. OPS TESTS GOOD REF FIM 49-40 TASK 825 PARA C & D STEPS 1 & 2.

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