# SDR UALA2012082704808

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 24, 2012
- Submitted: September 14, 2012
- Operation: Air carrier
- Aircraft: N596UA
- Make and model: Boeing 757222
- Aircraft serial: 28749
- Aircraft time: 56,473 hours, 15,824 cycles
- Engine: Pwa PW2037
- System (JASC): [4920 · APU Core Engine](https://openairdocs.org/jasc/4920)
- Part: Apu
- Part number: 331200E
- Part serial: 60227331
- Condition: Faulty
- Location: Apu Bay
- Stage of operation: IN
- 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/UALA2012082704808

## Discrepancy

APU FAULT FAILED TO START FIRST ATTEMPT.  ACCMP'D BITE ON ECU, HAD ABORTED START.  STARTER CIRCUIT FAULT.  CREW STARTED APU ON SECOND TRY.  START CONTACTOR, E-STARTER, START RELAY, ECU AND APU BAT CHRGR HAS BEEN REPLACED.  HISTORY INDICATES THAT APU ESN 60227 WAS REMOVED FROM ACFT 5439 FOR SAME CHRONIC REASON & PASSED TEST CELL DIAG.  HOWEVER PREVIOUS VISIT HAD IGV LINKAGE PROB.  REPLACE APU.  REPLACED APU PER TOD MM, OPS CHECK AND LEAK CHECK OKAY.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.