As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) APU CHARGER STATUS MESSAGE CIRCUIT BREAKER POPPED - ON TAXI OUT. WHEN MECHANIC RESET THE CIRCUIT BREAKER THE CONNECTOR PLUG ON TOP OF THE CHARGER CAUGHT FIRE. REPAIRED CONNECTOR PLUG BY REPINING ALL ASSOCIATED WIRES. REPLACED APU BATTERY & CHARGER. COMPONENT REPLACED ON TOP OF THE APU BATTERY CHARGER.