# SDR COEA2025073101901

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 30, 2025
- Submitted: July 31, 2025
- Operation: Air carrier
- Aircraft: [N901FX](https://openairdocs.org/aircraft/N901FX), registered now
- Make and model: Aerosp ATR 42-320
- Registry model: [Aerosp ATR 42-320](https://openairdocs.org/model/aerospatiale-aeritalia-atr-42-320) (OpenAirDocs)
- Aircraft serial: 172
- Aircraft time: 35,328 hours, 38,245 cycles
- System (JASC): [2130 · Cabin Pressure Control System](https://openairdocs.org/jasc/2130)
- Part: Acm
- Part number: 22044005
- Part serial: 101621R
- Condition: Seized
- Location: Nr 1
- Stage of operation: CR
- 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/COEA2025073101901

## Discrepancy

FLIGHT 7820, ENROUTE GTF-MSO   EXCESS CABIN ALTITUDE ALERT/WARNING LIGHT ILLUMINATED IN FLIGHT.  AFTER EXTENSIVE TROUBLESHOOTING, MAINTENANCE REPLACED THE #1 ACM AND TIC VALVE. ALL CHECKS GOOD.

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