# SDR ASAA2021021034071

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 10, 2021
- Submitted: February 12, 2021
- Operation: Air carrier
- Aircraft: [N586AS](https://openairdocs.org/aircraft/N586AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35189
- Aircraft time: 48,354 hours, 14,610 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Modulating Valve
- Part number: 3989083
- Part serial: 9188
- Condition: Faulted
- Location: Lt A/C Pack Bay
- Part time: 47,190 hours, 17,999 cycles
- Stage of operation: TX
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2021021034071

## Discrepancy

AFTER START ON RECALL GOT MASTER CAUTION, CONT CABIN ZONE TEMP. EXTINGUISHED WITH RESET. GROUNDED - YES. REMOVED AND REPLACED CONTROL CABIN TRIM MODULATING VALVE IAW B737-800 AMM 21-61-21-000-801 AND AMM 21-61-21-400-801, ETOPS GROUND FUNCTIONAL CHECK GOOD IAW AMM 21-61-00-740-801-002.

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