# SDR ASAA2019123081714

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 28, 2019
- Submitted: December 31, 2019
- Operation: Air carrier
- Aircraft: [N457AS](https://openairdocs.org/aircraft/N457AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 36355
- Aircraft time: 23,295 hours, 7,549 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Warning Light
- Condition: Illuminated
- Location: Rt A/C Pack
- Part time: 23,224 hours, 7,550 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/ASAA2019123081714

## Discrepancy

RIGHT PACK LIGHT ILLUMINATES WITH RECALL, EXTINGUISHES WITH MASTER CAUTION RESET. GROUNDED - YES. PERFORMED FIM 21-53 TASK 821 NO FAULTS FOUND. DUE TO 2X HISTORY AFTER RECENT REPLACEMENT OF LT PACK ZONE TEMP CONTROLLER SUSPECTED FAULTY LRU. PLACED THIS ITEM ON SOS. AS A PRECAUTION REPLACED L/H TEMP CONTROLLER REF AMM 21-61-20/401. OPS TEST PASSED NO DEFECTS NOTED. .

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