As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU PNEUMATIC FUNCTION INOP ( AUXILIARY POWER UNIT, PNEUMATIC FUNCTION )TRANSFERRED TO MDDR 129107 PER MEL 49-11-01-0,1 CAT "C", DUE 11JUN20 0710Z. CL PLACARDS INSTALLED. REMOVED AND REPLACED APU SURGE VALVE IAW AMM 49-53-01. THIS CLEARS MDDR 129107.