As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU WON'T START(THIS BECOMES DMI NR 142640 IAW MEL 49-11-01A CAT C DDD 01MAR21 A/C DOWNGRADED TO NON ETOPS 19FEB21- LOG PG 1339208 ITM 4 - RIV - PERFORMED BITE OF ECU IAW FIM 49-11 FT958. FAULTED "A/C START CIRCUIT" PERFORMED FIM 49-11 F/T 991 UP TO SHEET 2 BLOCK 23. REMOVED AND REPLACED APU START TRU IAW AMM 24-32-04. OPS CHECK GOOD IAW AMM 49-11-00 PERFORMED 3 SUCCESSFUL START. NO DEFECTS NOTED AT THIS TIME. THIS CLEARS DMI 142640.)