# SDR ASAA12511275

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 18, 2012
- Submitted: March 26, 2012
- Operation: Air carrier
- Aircraft: [N512AS](https://openairdocs.org/aircraft/N512AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 39043
- Aircraft time: 13,437 hours, 4,278 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Modulating Valve
- Part number: 3989083
- Part serial: 9373
- Condition: Faulty
- Location: Ac Bay
- Part time: 17,134 hours, 5,928 cycles
- Stage of operation: TX
- How discovered: O
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA12511275

## Discrepancy

DURING RECALL AFTER STARTING ENGINES AIR COND MASTER CAUTION LIGHT REMAIN ILLUMINATED ALONG WITH CONT CAB ZONE TEMP LIGHT.  RESETS WITH MASTER CAUTION RESET.  BITE CKD BOTH CONTROLLERS NR 2 CONTROLLER FAULTED FLT DECK TRIM VALVE.  REPLACED R2 COCKPIT ZONE TRIM MODULATING VALVE REF 21 61 21MM.  OPS NORMAL FAULT REMOVED FROM NR 2 PRESS CONTROLLER.

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