What was found
WHILE TRANSFERRING BETWEEN APU AND EXT PWR BUSSES, ELEC ANNUNCIATOR ON P5-5 PANEL CAME ON. SPCU INOPERATIVE SHOWS, WILL NOT RESET. ACFT GROUNDED. REMOVED & REPLACED THE STANDBY POWER CONTROL UNIT IAW AMM 24-34-11. OPS NORMAL .
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
WHILE TRANSFERRING BETWEEN APU AND EXT PWR BUSSES, ELEC ANNUNCIATOR ON P5-5 PANEL CAME ON. SPCU INOPERATIVE SHOWS, WILL NOT RESET. ACFT GROUNDED. REMOVED & REPLACED THE STANDBY POWER CONTROL UNIT IAW AMM 24-34-11. OPS NORMAL .