As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DEN - ON FLIGHT NUMBER 4321, UPON APU STARTUP RECEIVED APU OVERTEMP WARNING. COMPLETED CHECKLIST. MAINTENANCE PERFORMED APU STARTUP ON RAMP, APU STARTED NORMALLY. NO PARTS REPLACED. OPERATIONAL CHECK GOOD. AIRCRAFT RETURNED TO SERVICE.