# SDR ASAA2018120327172

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 30, 2018
- Submitted: December 4, 2018
- Operation: Air carrier
- Aircraft: [N448AS](https://openairdocs.org/aircraft/N448AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 36356
- Aircraft time: 10,754 hours, 3,594 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Control Valve
- Condition: Faulted
- Location: Lt A/C Pack
- Stage of operation: TX
- 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/ASAA2018120327172

## Discrepancy

LEFT PACK LIGHT ON RECALL DURING AFTER START CHECK. EXTINGUISHED WHEN MC PRESSED (PRIMARY OR SECONDARY CONTROLLER FAILURE). GROUNDED - YES. BITE OF LPFTC SHOWS TEMP CTR VALVE FAULT WITH CODES 21-51264 AND 21-51267. ACCOMPLISHED B737-900 FIM 21-53 TASK 803. FAULT SELF RESTORED & OPS NORMAL.

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