As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ATTEMPTED APU START, DURING START UP APU WENT TO AUTO SHUTDOWN. PERFORMED MULTIPLE ATTEMPTS WITHIN TOLERANCE TO START. EACH ENDING IN AUTO SHUTDOWN. GROUNDED - YES. ACCOMPLISHED BITE CHECK, FOUND FAULT CODE 49-41010. NO ACCELERATION SHUTDOWN. PERFORMED GVI ON EXHAUST SECTION OF APU. FOUND TURBINE BLADES TO ALL BE DAMAGED. APU REPLACED PER TASK CARD 78349010. LK AND OPS CK GOOD.