# SDR ASAA2023040842797

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 8, 2023
- Submitted: April 12, 2023
- Operation: Air carrier
- Aircraft: [N529AS](https://openairdocs.org/aircraft/N529AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35198
- Aircraft time: 45,873 hours, 13,541 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Modulating Valve
- Part number: 3989058
- Part serial: 22238
- Condition: Faulted
- Location: Lt Ecs Bay
- Part time: 27,357 hours, 5,408 cycles
- Stage of operation: TX
- 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/ASAA2023040842797

## Discrepancy

DURING AFTER START CHECK LEFT PACK LIGHT ILLUMINATED ON RECALL. LIGHT EXTINGUISHED WITH MASTER CAUTION RESET. GROUNDED - YES. REMOVED AND REPLACED LEFT TCV, V141 B737-800 AMM 21-51-10.

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