As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI IN TRIED STARTING APU RECEIVED APU FAULT LIGHT. GROUNDED - YES. APU WAS CONTINUOUS RUN IN FLIGHT. CREW TURNED OFF PRIOR TO TOP OF DESCENT. APU START ATTEMPTS WAS AFTER LANDING. NO SECOND ATTEMPT MADE. APU BITE ACCOMPLISHED. CODE 49-31171 DISPLAYED. FAULT LIGHT WAS NOT PRESENT. ACCOMPLISHED FIM 49-31 TASK 808 NORMAL APU START AND OPS CHECK. TWO TIMES IAW AMM 49-11-00. GROUND FUNCTIONAL TEST OK.