# SDR CALA2012110600746

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: November 6, 2012
- Submitted: November 6, 2012
- Operation: Air carrier
- Aircraft: [N57111](https://openairdocs.org/aircraft/N57111), registered now
- Make and model: Boeing 757224
- Aircraft serial: 27301
- Aircraft time: 75,339 hours, 16,253 cycles
- System (JASC): [2450 · AC Power Distribution System](https://openairdocs.org/jasc/2450)
- Part: Control Unit
- Part number: 734285E
- Part serial: 02163
- Condition: Malfunctioned
- Location: Elec Bay
- Stage of operation: CR
- How discovered: O
- Nature of condition: G, J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2012110600746

## Discrepancy

INFLIGHT AT FL350, BOTH LT &  RT UTILITY BUSS AMBER LIGHTS CYCLED ON AND OFF 4 TIMES IN A 30 MINUTE PERIOD.  DIVERTED BACK TO DEPARTURE.  TROUBLESHOT IAW FIM 24-20-00, FOUND BPCU INTERMITTENT. R & R BPCU IAW AMM 24-41-03-404-008. UTILITY BUSS SYS OPS CHECKED NORMAL IAW AMM 24-22-00.  ACFT OK TO CONTINUE.

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