As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DIVERSION, APU FIRE WARNING LIGHT ILLUMINATED IN FLT. APU FIRE BOTTLE DISCHARGED. APU FIRE WARNING LIGHT STILL ILLUMINATED MULTIPLE TIMES AFTER BOTTLE DISCHARGED. FOUND APU AFT TAILPIPE HARNESS CONNECTORS GROUNDING OUT THRU CERAMIC. REMOVED AND REPLACED APU AFT TAILPIPE HARNESS PER MM.