# SDR ASAA2018072425509

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 22, 2018
- Submitted: July 24, 2018
- Operation: Air carrier
- Aircraft: [N506AS](https://openairdocs.org/aircraft/N506AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35690
- Aircraft time: 38,506 hours, 11,814 cycles
- System (JASC): [2150 · Cabin Cooling System](https://openairdocs.org/jasc/2150)
- Part: Warning System
- Condition: False Activation
- Location: Cockpit
- Stage of operation: DE
- 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/ASAA2018072425509

## Discrepancy

AT TOP OF DESCENT UPON MASTER RECALL, LEFT PACK ILLUMINATED. UPON RESET OF MASTER CAUTION, LEFT PACK LIGHT CLEARED. GROUNDED - YES. CONFIRMED LT PACK OVHD ANNUNC ILLUM W/MSTR RECALL. PERF'D BITE TEST OF PACK/ZONE TEMP CONTROLLERS PER AMM 21-61-00. UPON INITIAL EVAL FOUND CONTLR NR 1 W/"TCV THIS PACK" RED FAULT LAMP ON IN PREVIOUS FLIGHT FAULTS. CONTINUED W/TEST AND CONTLR NR 1 OPS NRML - FAULT LAMP EXTINGUISHED. SUBSEQUENT TEST OF BOTH CONTLRS PER ABOVE AMM REF OPS NRML W/NO FAULTS DISPLAYED. L PACK ANNUNC NOW REMAINS EXTINGUISHED W/MSTR RECALL.

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