# SDR ASAA2015030910897

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 9, 2015
- Submitted: March 11, 2015
- Operation: Air carrier
- Aircraft: [N518AS](https://openairdocs.org/aircraft/N518AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35693
- Aircraft time: 23,612 hours, 7,059 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Valve
- Part number: 3989083
- Part serial: 8318
- Condition: Malfunctioned
- Location: A/C Bay
- Part time: 33,391 hours, 10,282 cycles
- Stage of operation: TX
- How discovered: 9
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2015030910897

## Discrepancy

CONTROLLER CABIN ZONE TEMP LIGHT ILLUMINATED UPON RECALL, EXTINGUISHES UPON MASTER CAUTION RESET.  ACFT GROUNDED.  PERFORMED TEMP CONTROLLER BITE, NR 1 AND NR 2 TEMP CONTROLLERS BOTH SHOW FLT DECK TRIM VALVE FAULTS ON BITE AND PREVIOUS FLTS.  REPLACED CONTROLLER CABIN ZONE TRIM AIR MODULATING VALVE REF MM 21-61-21. PERFORMED BITE TEST ON PACK/ZONE TEMP CONTROLLERS REF MM 21-61-00.  NO FAULTS NOTED.

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