# SDR ASAA2022032637780

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 26, 2022
- Submitted: March 30, 2022
- Operation: Air carrier
- Aircraft: [N481AS](https://openairdocs.org/aircraft/N481AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44106
- Aircraft time: 24,660 hours, 7,782 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: None
- Part number: UNKNOWN
- Condition: None
- Stage of operation: NR
- How discovered: V
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2022032637780

## Discrepancy

CONT CABIN ZONE TEMP LIGHT WITH MASTER CAUTION RECALL. GROUNDED - YES. PERFORMED BITE TEST ON BOTH ZONE TEMP CONTROLER PER B737-900 FIM 21-62 TASK 801. FOUND FAULT ON #1 ZONE TEMP CONT ( SRADA INLET) AND FAULT ON #2 ZONE TEMP CONT (FLT DECK TRIM VALVE). BOTH FAULTS CLEARED ON CONTROLLERS, RAN PACKS TWICE AND NO FAULTS NOTED AND SYS OPERATED NORMALLY.

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