As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU WILL NOT START. OPENED INLET DOOR MANUALLY VIA MANUAL DRIVE IAW AMM 49-15-06. FOUND ICE & SNOW STUCK IN INLET ACTUATOR AREA. APU INLET DOOR FROZEN ICED SHUT. RAN APU & MELTED COMPARTMENT. CYCLED APU SEVERAL TIMES, OPERATIONS NORMAL.