# SDR CALA2022092302445

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 23, 2022
- Submitted: September 23, 2022
- Operation: Air carrier
- Aircraft: [N73278](https://openairdocs.org/aircraft/N73278), registered now
- Make and model: Boeing 737
- Aircraft serial: 31596
- Aircraft time: 57,213 hours, 20,392 cycles
- System (JASC): [4900 · Airborne Auxiliary Power Unit (APU) System](https://openairdocs.org/jasc/4900)
- Part: None
- Part number: 28B5459
- Part serial: 60A0566
- Condition: Shutdown
- Location: Other
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2022092302445

## Discrepancy

APU FAULT LIGHT LIGHT ON, APU OPERATES WITHOUT A PROTECTIVE SHUT DOWN DIRECTLY DEFERRED BY TOMC. ONBOARD FLIGHT MECHANIC PERFORMED DDP. DISPATCH DESK: 53   NAME: A.C  DATE: 20-SEP-22- NOC      DESK: OPB  NAME: C.A  DATE: 20-SEP-22- DEFERRED DIRECTLY BY TOMC REMOVE AND REPLACED APU STARTER GENERATOR IAW AMM 49-41-21 OP CHECK AND LEAK CHECK GOOD DEFER CLEARED AND PLACARD REMOVED. ROTABLE PARTS CHANGE WAS INDICATED - TT # 1876832  SN OFF 0566 GENERATOR, APU,  OFF 29-2421-9-0004 0566 ON 29-2421-9-0004 0007

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