As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU FAULT LIGHT CAME ON DURING START ON GROUND. QRH ACCOMPLISHED FIVE MINUTES, LIGHT OUT AND RE-START. OPS NORM. ACFT GROUNDED. ACFT GROUNDED. PERFORM APU BITE PROCEDURE REF. FIM TASK 49-60 TASK 801. FOUND FAULT CODE 49-41180 LOGGED. CLEARED FAULT. PERFORMED SUBSEQUENT APU START. FAULT REMAINED CLEARED. TSR ISSUED. REPLACED EXCITER, IGNITION LEAD AND PLUG PER AMM 49-41-31. OPS CHECK GOOD NO FAULT REGISTERED.