# SDR ASAA2017080821580

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 8, 2017
- Submitted: August 10, 2017
- Operation: Air carrier
- Aircraft: [N478AS](https://openairdocs.org/aircraft/N478AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44105
- Aircraft time: 8,356 hours, 2,795 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Actuator
- Part number: 676000141
- Part serial: 676000145128
- Condition: Failed
- Location: Lt Ram Air Inlet
- Part time: 6,243 hours, 2,137 cycles
- 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/ASAA2017080821580

## Discrepancy

LEFT PACK LIGHT ILLUMINATES WITH MASTER CAUTION RECALL AND EXTINGUISHES WHEN MASTER CAUTION SYSTEM IS RESET.  ACFT GROUNDED. CONFIRMED FAULT, LT PACK/ZONE TEMP CONTROLLER BITE TEST IAW AMM 21-61-00. FAILED LT RAM AIR INLET ACTUATOR. REMOVED & REPLACED THE ACTUATOR IAW AMM 21-51-21. GROUND FUNCTIONAL CHECKED NORMAL.

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