As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE FLIGHT THE CREW RECEIVED -APU LOOP A FAULT- AND 2 MINUTES LATER APU FIRE BOTTON ILLUMINATED RED WITH NO ECAM MESSAGE. CREW AFTER 10 SECONDS DISCHARGED THE FIRE BOTTLE IN COMPLIANCE WITH FCOM AND THE LIGHT INDICATED -DISCHARGED-. DUE THE FIRE LIGHT REMAINED ILLUMINATED THE AIRCRAFT DIVERTED TO DEN. THE AIRCRAFT FLOWN BACK TO JFK UNDER MEL 26-13-01, 49-10-01 & 26-22-01. AT JFK THE DISCHARGED FIRE BOTTLES WERE REPLACED. THE DISCREPANCY WAS CORRECTED BY REPLACING THE APU FIRE DETECTION UNIT.