# SDR ASAA2020122633746

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 26, 2020
- Submitted: December 29, 2020
- Operation: Air carrier
- Aircraft: [N409AS](https://openairdocs.org/aircraft/N409AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41733
- Aircraft time: 28,973 hours, 9,370 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Warning Light
- Condition: False Activation
- Location: Lt A/C Pack
- Stage of operation: NR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020122633746

## Discrepancy

LEFT PACK LIGHT ON MASTER CAUTION RECALL. GOES OUT ON MASTER CAUTION RESET.  GROUNDED-YES.  PACK ZONE TEMP CONTROLLER BITE, PER B737-900 FIM 21-62 TASK 801.  SHOWED BIT AND PREV FLT FAULTS FOR LEFT PACK RAM AIR ACTUATOR, BUT VERIFY TEST DID NOT CONFIRM FAULT.  ACCOMPLISHED RAM AIR SYSTEM OPERATIONAL TEST, PER B737-800 AMM 21-51-00-730-802.  SEVERAL TIMES ALL TESTS PASS.

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