As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED VIA ACARS MSG THAT APU WOULD NOT START AND FAULT LIGHT ILLUMINATED AT 33,000. APU STARTED ON 3RD ATTEMPT. ACFT GROUNDED. APU BITE SHOWS NO CURRENT FAULTS & MSG 49-41010 (NO ACCELERATION) FOR THE PREVIOUS 2 FAILED STARTS. (COLD SOAKED). APU BITE PERFORMED IAW FIM REF 49-60-00-810-801. APU OPS NORMAL ON GROUND. R & R APU FUEL CONTROL UNIT REF AMM 49-31-11-000-801 AND AMM REF 49-31-11-400-801. OPS AND LEAK CKD GOOD. PERFORMED APU BITE CK REF AMM 49-61-00-700-801, NO CURRENT FAULTS NOTED.