# SDR ASAA2015033111169

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 31, 2015
- Submitted: March 31, 2015
- Operation: Air carrier
- Aircraft: [N584AS](https://openairdocs.org/aircraft/N584AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35682
- Aircraft time: 4,031 hours, 1,334 cycles
- System (JASC): [4900 · Airborne Auxiliary Power Unit (APU) System](https://openairdocs.org/jasc/4900)
- Part: Data Unit
- Part number: 38762871
- Part serial: GE4703
- Condition: Failed
- Location: Apu
- Part time: 8,928 hours, 10,701 cycles
- 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/ASAA2015033111169

## Discrepancy

APU FAULT CODE 49-72104 DMM SHOWS CIRCUIT FAILURE LOGGED IN FMC/CDU.  ACFT GROUNDED. APU FAULT CODE 49-72104 SHOWS UNDER MAINT HISTORY ON ALMOST EVERY OF LAST 33 STARTS. R & R APU DATA MEMORY MODULE REF MM 49-72-11.  OPS NORMAL REF SAME.  PERFORMED 3 EA SPU STARTS, SHUTDOWNS W/ NO RECURRENCE OF FAULT UNDER CURRENT STATUS OR MAINTENANCE.

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