As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: DUE TO ELECTRICAL FIRE ON APU START DISCHARGED APU FIRE BOTTLE. REMOVED AND REPLACED APU FIRE EXTINGUISHING BOTTLE (11WF) IAW AMM 26-22-41-0401. OPS TEST NORMAL. ALSO INSPECTED APU AND APU COMPARTMENT IAW AMM 49-00-00-200-001-A. NO DEFECTS NOTED.