As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PRIOR TO DEPARTURE THE APU SHUTDOWN AND THE APU FIRE BOTTLE DISCHARGE LIGHT CAME ON. INSPECTED THE APU COMPARTMENT AND FOUND NO EVIDENCE OF APU FIRE, THERE WAS EVIDENCE THAT THE APU FIRE BOTTLE HAD DISCHARGED. REPLACED APU FIRE BOTTLE, PERFORMED BITE ON THE ECU PER FIM 49-11-00 FIG 103, NO FAULTS. INSPECTED APU COMPARTMENT AND APU EXHAUST, NO DAMAGE OF EVIDENCE OF A FIRE FOUND.