As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TR UNIT LIGHT ILLUMINATED AFTER POWER TRANSFER FROM APU GENERATOR TO ENGINE GERNERATORS. ACFT GROUNDED. CYCLED POWER ON AND OFF SEVERAL TIMES, AND TRANSFERRED POWER BETWEEN APU AND GROUND WITH NO DISCREPANCIES NOTED. ACCOMPLISHED FIM 24-31, TASK 826 WITH NO DEFECTS NOTED. NO FAULTS LOGGED. SYSTEMS OP NORMAL. NO HISTORY 30 DAYS. GROUND VERIFICATION SATISFACTORY.