# SDR ASAA12511271

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 18, 2012
- Submitted: March 20, 2012
- Operation: Air carrier
- Aircraft: [N558AS](https://openairdocs.org/aircraft/N558AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35177
- Aircraft time: 18,552 hours, 6,477 cycles
- System (JASC): [4930 · APU Engine Fuel and Control](https://openairdocs.org/jasc/4930)
- Part: Fcu
- Part number: 4419215
- Part serial: CUC13915
- Condition: Defective
- Location: Apu
- Part time: 7,264 hours, 5,811 cycles
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA12511271

## Discrepancy

APU INDICATES ZERO FREQS & 1 VOLT AT CRUISE (POST CP).  PER FIM 49 30 00 810 805 C/W FCU RESOLVER CIRCUIT FAULT ISOLATION:  CONNECTOR P22 PINS 10 TO 12 CONTINUITY READS OPEN (SHOULD READ 30 200 OHMS) FUEL CONTROL UNIT REPLACEMENT REQ'D.  REMOVED AND REPLACED APU FUEL CONTROL UNIT REF M/M 49 31 11, OPS AND LEAK CHECKS GOOD.

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