As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU INOP, NO START ON GATE. ATTEMPTED START ON ARRIVAL. NO VOLTAGE DROP ON START, APU DOOR OPEN NORMALLY. WITH APU MAINT SWITCH IN TEST NO FAULTS ON APUC. ACPD FIM 49-40 TASK 812, CONFIRMED RELAY K24494 WORKING PROPERLY AND 28VDC ON TERMINAL E2 AT ELEC STARTER. NEED TO REPLACE ELEC STARTER. REPLACED STARTER. OP CHECKS NORMAL.