# SDR ASAA2018020323395

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 3, 2018
- Submitted: February 5, 2018
- Operation: Air carrier
- Aircraft: [N440AS](https://openairdocs.org/aircraft/N440AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 41705
- Aircraft time: 17,023 hours, 5,663 cycles
- System (JASC): [4990 · APU Oil System](https://openairdocs.org/jasc/4990)
- Part: Pressure Switch
- Part number: 38762552
- Condition: Faulted
- Location: Apu Oil
- Stage of operation: IN
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2018020323395

## Discrepancy

WHILE ACCOMPLISHING AN APU BITE PROCEDURE IAW FIM 49-60 TASK 801,  FOR AIRCRAFT HISTORY OF BLUE MAINTENANCE LIGHT ON WITH OIL LEVEL FOUND FULL, FAULT HISTORY SHOWS NO FAULTS. CURRENT STATUS LAST 17 CYCLES, FAILED TEST, MESSAGE 49-94226 FOR LOW OIL PRESSURE SWITCH, SHOWS OPEN CIRCUIT.  ACFT GROUNDED.  ACCOMPLISHED FIM 49-90 TASK 805, REMOVED & REPLACED THE LOW OIL PRESSURE SWITCH IAW AMM 49-94-22, LEAK & OPS CHECKED NORMAL. CURRENT STATUS NOW SHOWS NO FAULTS.

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