# SDR ASAA2021112236684

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 22, 2021
- Submitted: November 24, 2021
- Operation: Air carrier
- Aircraft: [N517AS](https://openairdocs.org/aircraft/N517AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35197
- Aircraft time: 46,851 hours, 13,684 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Modulating Valve
- Part number: 3989083
- Part serial: 6684
- Condition: Inoperative
- Location: Left Ecs Bay
- Part time: 64,025 hours, 21,602 cycles
- Stage of operation: NR
- How discovered: V
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2021112236684

## Discrepancy

ILLUMINATION OF THE ZONE TEMP CONT CAB ON RECALL OF MASTER CAUTION. EXTINGUISHES ON 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 21-61-00-700-806-002.

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