# SDR ASAA2017103122393

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 31, 2017
- Submitted: November 2, 2017
- Operation: Air carrier
- Aircraft: [N493AS](https://openairdocs.org/aircraft/N493AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41727
- Aircraft time: 6,072 hours, 2,053 cycles
- System (JASC): [2160 · Cabin Temperature Control System](https://openairdocs.org/jasc/2160)
- Part: Control Module
- Part number: 6937324378
- Part serial: F08748
- Condition: Failed
- Location: Cockpit Temp
- Part time: 6,063 hours, 2,049 cycles
- Stage of operation: NR
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2017103122393

## Discrepancy

CONTROL CABIN TEMPERATURE CONTROLLER PRODUCES FULL HOT AIR IN ANY POSITION.  WHEN IN OFF POSITION IT MAINTAINS A DUCT TEMPERATURE OF 9 DEGREES C.  ACFT GROUNDED. VERIFIED PROBLEM.  BITE CHECKED BOTH ZONE TEMP CONTROLLERS IAW AMM 21-61-00. NO FAULTS.  VERIFIED CONTROL CABIN SENSOR FAN IS OPERATING & FILTER IS CLEAN. WITH CONTROL CABIN SELECTOR KNOB AT 11:00 POSITION DUCT TEMP DRIVES FULL HOT.  REMOVED & REPLACED TEMP CONTROL MODULE P5-17 IAW AMM 21-61-15. OPS NORMAL.  CONTROL CABIN TEMP INCREASES & DECREASES SMOOTHLY.

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