As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU WON’T START AFTER 2ND ATTEMPT. TRIED CYCLING THE APU CONTROL BREAKERS, NO HELP. INLET DOOR STUCK IN THE PARTIALLY OPEN POSITION & APU IS INOPERATIVE. IAW MEL CB L41 & L42 OPENED & TAGGED. ACCOMPLISHED TSM 49-00-00-810-899 -A REPLACED APU MOTOR STARTER IAW AMM 49-42-51PB401. APU STARTED TWICE WITH NORMAL OPERATIONS OK FOR SERVICE.