As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED THAT 1.5 HRS INTO FLT, FLT ATTD REPORTED NO PWR TO AFT GALLEY. AT 2.0 HRS INTO FLT BOTH LT & RT UTILITY BUSSES TRIPPED OFF. IAW FIM CREW CYCLED UTILITY BUS SWITCHES ALL PWR RESTORED & OPERATIONS NORMAL. REPLACED BPCU IAW MM24-41 -03, SHOOK OUT WIRES BEHIND BPCU, RAN ENGS & LOADED GALLEY BUSSES. UNABLE TO DUPLICATE UTILITY BUS TRIP. RAN RECIRCULATING FANS ALSO.