# SDR COZA20140810045

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 6, 2014
- Submitted: August 10, 2014
- Operation: Air carrier
- Aircraft: [N737KA](https://openairdocs.org/aircraft/N737KA), registered now
- Make and model: Boeing 737-7BX
- Registry model: [Boeing 737-7BX](https://openairdocs.org/model/boeing-737-7bx) (OpenAirDocs)
- Aircraft serial: 30740
- Aircraft time: 27,144 hours, 16,661 cycles
- System (JASC): [2133 · Pressure Regulator/Outflow Valve](https://openairdocs.org/jasc/2133)
- Part: Outflow Valve
- Part number: 40631997201AB
- Part serial: 0010547
- Condition: Faulty
- Location: Cabin Pressure
- Stage of operation: LD
- How discovered: O
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/COZA20140810045

## Discrepancy

THE AUTO FUNCTION OF THE CABIN PRESS CONTROL FAILED.  TROUBLESHOOTING USING THE FAULT ISOLATION MANUAL & BITE TESTS FOUND A FAULT ON THE OUTFLOW VLV.  THE OUTFLOW VLV WAS REPLACED & FAULTS DID NOT RETURN.  OPERATIONAL TESTS OF THE CABIN PRESS CONTROL SYS WERE NORMAL.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.