# SDR ASAA2018011523146

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 15, 2018
- Submitted: January 17, 2018
- Operation: Air carrier
- Aircraft: [N403AS](https://openairdocs.org/aircraft/N403AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41730
- Aircraft time: 20,906 hours, 6,867 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Control Valve
- Part number: 3989083
- Part serial: 186
- Condition: Faulted
- Location: Lt A/C Pack
- Part time: 114 hours, 45 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/ASAA2018011523146

## Discrepancy

LEFT PACK LIGHT ON RECALL, RESET WITH MASTER CAUTION.  ACFT GROUNDED.   ACCOMPLISHED A BITE TEST, FOUND THE LEFT PACK TCV FAULT LIGHT, LIGHT WOULD NOT RESET, BITE TESTED THE RT CONTROLLER PASSED. REMOVED & REPLACED THE LT PACK TCV IAW AMM 21-51-10-000-801, AND 21-51-10-400-801. LEAK CHECKED GOOD.  COMPLETED PACK/ZONE TEMPERATURE CONTROLLER BITE TEST, OPS CHECKED GOOD AND NO DEFECTS NOTED IAW AMM 21-51-00-700-803.

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