As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU WOULD NOT START. APU BLEED STATUS THEN APU FAULT, CYCLED NO LUCK. RESTART APU IS GOOD, BUT APU BLEED AIR MSG STAY ON, AIR START. APU STILL NO HELP. DEFER PER MEL. APU ELEC SUPPLY IS GOOD, BUT AIR SUPPLY IS NOT USEABLE. RPLC'D APU CHECK VALVE PER MM. OPS CHECKS NORMAL.