As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU FAULT LIGHT ILLUMINATED DURING START. PERFORMED APU BITE TEST. DISPLAYED MESSAGE 49-41255 START POWER UNIT SHOWS HIGH TEMPERATURE. NO APU ROTATION SHUTDOWN. ACFT GROUNDED. TROUBLESHOT IAW FIM 49-40 TASK 815. COULD NOT DUPLICATE DISCREPANCY. FOUND SAME MESSAGE FLAGGED 15 LEGS AGO. REMOVED AND REPLACED APU START POWER UNIT, FOR TROUBESHOOTING. OPS CHECKS GOOD. REFERENCE APPLICABLE STEPS IAW AMM 49-41-71.