As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAXI OUT APU AUTO SHUT DOWN, GOT APU FAULT INDICATION AND BURNING SMELL THROUGHOUT AIRCRAFT. APU EXPERIENCED INTERNAL FAILURE, EXPANDED CASE, AND DAMAGED INLET DOOR AND SURROUNDING PANEL. REPLACED APU AND INLET DOOR PANEL ASSEMBLY. REPAIRED WIRES DAMAGED BY DOOR PANEL EXPANSION. PERFORMED DUCT BURNOUT PROCEDURES AND REPLACED COALESCER BAGS.