# SDR 96ZZZX4880

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 10, 1996
- Submitted: March 26, 2000
- Operation: General aviation
- Aircraft: [N425BZ](https://openairdocs.org/aircraft/N425BZ), registered now
- Make and model: Cessna 425
- Registry model: [Cessna 425](https://openairdocs.org/model/cessna-425) (OpenAirDocs)
- Aircraft serial: 4251040
- System (JASC): [4960 · APU Controls](https://openairdocs.org/jasc/4960)
- Part: Relay
- Part number: 2T29941
- Condition: Failed
- Location: Apu Cut Out
- Stage of operation: CR
- Nature of condition: H
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/96ZZZX4880

## Discrepancy

RELAY CONTROLS THE APU CUT-OUT RELAY TO PREVENT USE OF WINDSHIELD HEAT WITHOUT THE GENERATOR OR APU ON-LINE.  THIS RELAY SHORTED INTERNALLY WHICH POSSIBLY SENT A FALSE SIGNAL TO THE GCU WHICH CAUSED THE GENERATORS* TO GO OFF LINE IN-FLIGHT.  AFTER EXTENSIVE TROUBLESHOOTING WITH CESSNA TECH SUPPORT, COULD NOT EXPLAIN WHY THIS HAPPENED IN-FLIGHT NOR COULD FIND ANY OTHER REPEATABLE CAUSE.  ALL OTHER SYSTEMS OPERATE PROPERLY.  *BOTH GENERATORS WENT OFF-LINE AND COULD NOT BE RESET.

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