# SDR ASAA2019022028261

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 20, 2019
- Submitted: February 22, 2019
- Operation: Air carrier
- Aircraft: [N478AS](https://openairdocs.org/aircraft/N478AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 44105
- Aircraft time: 14,431 hours, 4,798 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Warning System
- Condition: False Activation
- Location: Cockpit
- Stage of operation: NR
- 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/ASAA2019022028261

## Discrepancy

CONT CAB ZONE TEMP LIGHT ILLUM ON RECALL. ZONE TEMP LIGHT EXT WHEN MASTER CAUTION WAS RESET. GROUNDED - YES. RESET SYSTEM AND RAN BOTH PACKS FOR 20 MINUTES WITH APU AIR, THEN TESTED SYSTEM PER AMM 21-61-00-700-802-002, BOTH PACK/ZONE TEMPERATURE CONTROLLERS BITE TEST PASSED. NO AIRCRAFT CONFIGURATION CHANGE.

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