As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING APU START MAINTENANCE MESSAGE 49-41250, START CONVERTER UNIT SHOWS START SYSTEM INOPERATIVE. FOUND 18 LOGGED FAULTS OF THIS MESSAGE. ACFT GROUNDED. PERFORMED FIM TASK 49-40, TASK 811. R & R APU START CONVERTER UNIT, INSTALLATION TEST PASSED, REF AMM 49-41-61.