As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING PERFORMANCE OF EPSU (12WL) FUNCTIONAL TEST, THE MECHANIC NOTED A POWER SUPPLY FAULT ON THE MDCU. THE EPSU WAS REPLACED, IAW AMM 33-51-38 PB 401 AND OPERATIONS CHECKED OKAY. PART TOTAL TIMES AND TOTAL CYCLES WILL BE PROVIDED AT A LATER DATE. REFERENCE LOG BOOK PAGE 308363, HOURS AND CYCLES FOR THE PART HAVE BEEN ADDED 01/11/08.