# SDR ASAA2018082525911

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 25, 2018
- Submitted: August 27, 2018
- Operation: Air carrier
- Aircraft: [N428AS](https://openairdocs.org/aircraft/N428AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 36353
- Aircraft time: 9,924 hours, 3,327 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Control Valve
- Part number: 3989085
- Part serial: 20534
- Condition: Failed
- Location: Lt A/C Pack
- Part time: 13,699 hours, 4,057 cycles
- Stage of operation: NR
- How discovered: O
- Nature of condition: N
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2018082525911

## Discrepancy

LEFT PACK LIGHT ILLUMINATED,  WHEN MASTER CAUTION WAS RESET, THE LIGHT EXTINGUISHED.  ACFT GROUNDED. REMOVED & REPLACED THE TCV V139 IAW AMM 21-51-10-000/400-801.  PERFORMED AN OPS TEST IAW AMM 21-51-00-710-801. CHECKED GOOD. NO FAULTS SHOWED. OPS NORMAL.

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