# SDR ASAA2020021833187

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 13, 2020
- Submitted: February 19, 2020
- Operation: Air carrier
- Aircraft: [N581AS](https://openairdocs.org/aircraft/N581AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35188
- Aircraft time: 48,417 hours, 14,468 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Filter
- Condition: Dirty
- Location: Temp Sensor
- 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/ASAA2020021833187

## Discrepancy

CONT CAB ZONE TEMP ILLUMINATES W/ RECALL AND EXTINGUISHES W/ MASTER CAUTION. GROUNDED - YES. VERIFIED ZONE TEMP LIGHT COMES ON DURING RECALL. BITE TESTED BOTH PZTC1+2 IAW B737-800 AMM 21-61-00-700-806-002. LIGHT FOR FLIGHT DECK TRIM VALVE SHOWS ON "BIT, CLEARED ON "VERIFY" FOR PZTC#2. NO OTHER DEFECTS. LIGHT NO LONGER SHOWS ON RECALL. RAN BOTH PACKS INDEPENDENTLY FOR 10-15 MINS EACH. RE RAN BITE CHECK, NO FAULTS FOUND. CLEANED CONT CAB TEMP SENSOR FILTER IAW AMM 21-61-06-100-801.

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