# SDR AALA201907229031

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 19, 2019
- Submitted: July 23, 2019
- Operation: Air carrier
- Aircraft: [N974UY](https://openairdocs.org/aircraft/N974UY), registered now
- Make and model: Airbus A321-231
- Registry model: [Airbus A321-231](https://openairdocs.org/model/airbus-a321-231) (OpenAirDocs)
- Aircraft serial: 4898
- Aircraft time: 27,589 hours, 10,380 cycles
- System (JASC): [7930 · Engine Oil Indicating System](https://openairdocs.org/jasc/7930)
- Part: Concentrator
- Part number: 350E5500204
- Part serial: 0E5011729
- Condition: Erratic
- Location: Zone 100
- Part time: 22,895 hours, 8,801 cycles
- Stage of operation: CL
- How discovered: O
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA201907229031

## Discrepancy

AIRCRAFT WAS GROUNDED: FLIGHT RETURNED TO PHL ON ACCOUNT OF NUMBER ONE ENGINE OIL PRESSURE INDICATION. AN EMERGENCY WAS DECLARED.  ENG 1 OIL PSI GAUGE WENT BETWEEN 100 AND 0 PSI AND THEN AMBER XX'S. IT WAS INTERMITTENT UNTIL LANDING. MAINTENANCE INSTALLED NEW OIL PRESSURE TRANSMITTER, NO HELP. DISCOVERED A LOOSE CONNECTOR, TIGHTENED CONNECTOR, NO HELP. REPLACED #4 BEARING OIL PRESSURE TRANSDUCER AND CONNECTOR 4005ENA, NO HELP. MAINTENANCE REPLACED THE SYSTEM DATA ACQUISITION CONCENTRATOR, ALL INDICATIONS RETURNED TO NORMAL. MAINTENANCE ALSO REPORTS THE SDAC WAS SWAPPED FROM 2 TO 1 AND CHECKED GOOD, AND WHEN PUT BACK TO ORIGINAL CONFIG. ALSO CHECKED GOOD. MAINTENANCE SUSPECTS THE FAULT WAS LATCHED INTO THE SDAC, HOWEVER THIS IS JUST A THEORY.

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