As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EXPERIENCE AN APU TAILPIPE FIRE. APU SHUTDOWN FAULT LIGHT DURING WALKAROUND, IMMEDIATELY AFTERWARDS FOUND SMOKE COMING FROM APU TAILPIPE AND FLAMES. APU SHUTDOWN. FIRE BOTTLES WERE NOT DISCHARGED. MAINTENANCE INSPECTED APU, NO DAMAGE FOUND. R & R ECU CONTROLLER IAW AMM 49-61. OPS CHECKED GOOD.