# SDR CA190307001

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 1, 2019
- Submitted: August 14, 2020
- Operation: General aviation
- Make and model: Bombdr DHC8400
- Aircraft time: 19,794 hours
- System (JASC): [2120 · Air Distribution System](https://openairdocs.org/jasc/2120)
- Part: Check Valve
- Part number: 8209342
- Condition: Failed
- Location: Cabin Pressure
- Part time: 20,215 hours
- Stage of operation: NR
- How discovered: 9
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CA190307001

## Discrepancy

(CAN) FLIGHT CREW REPORTED A CABIN PRESS CONTROLLER FAULT MESSAGE CLIMBING THROUGH 17000`. DIFFERENTIAL SHOWED 6 AND CABIN 2500` ALT. THIS WAS FOLLOWED BY 12000` WITH CONTROL AGAIN. MAINTENANCE TROUBLESHOOTING WAS ACCOMPLISHED AND ULTIMATELY THE GROUND CONNECTION CHECK VALVE WAS REPLACED IAW AMM 21-23-06-400-801. PX RUN COMPLETED IAW AMM 21-31-00-710-801. NO FURTHER FAULT WAS FOUND AND THE SYSTEM WAS CHECKED SERVICEABLE. AIRCRAFT HOURS: 20215:29. AIRCRAFT CYCLES: 20130. (TC# 20190307001)

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