# SDR UPS99531243

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 31, 1999
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: [N410UP](https://openairdocs.org/aircraft/N410UP), registered now
- Make and model: Boeing 757-24APF
- Registry model: [Boeing 757-24APF](https://openairdocs.org/model/boeing-757-24apf) (OpenAirDocs)
- Aircraft serial: 23732
- System (JASC): [7532 · Compressor Bleed Valve](https://openairdocs.org/jasc/7532)
- Part: Bleed Valve
- Condition: Inoperative
- Location: Lt Engine
- Stage of operation: CL
- Nature of condition: J
- Precautionary procedure: H
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UPS99531243

## Discrepancy

AIR TURN BACK, EICAS MSG CABIN ALTITUDE DISPLAYED.  CABIN ALT AND CABIN ALTITUDE LIGHTS ILLUMINATED.  ALSO, L ENG BLEED OFF MSG ON EICAS ALONG WITH L ENG BLEED AIR LIGHT ON.  DUCT PRESSURE AT ZERO.  DEFERRED LEFT ENGINE BLEED PER MEL 36-77-7.  PERFORMED BITE TEST PER 21-30-00, FIGURE 103, OF CABIN PRESSURE CONTROLLER WITH NO FAILURE NOTED.

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