As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FWD DRAIN PORT ON APU DRAIN MAST LEAKING OIL. GROUNDED - YES. REMOVED WITNESS DRAIN TEE ON SURGE CONTROL VALVE, FUEL CONTROL UNIT, IGV ACTUATOR. RUN APU AND FOUND OIL LEAKING FROM FCU DRAIN TEE. ALL TROUBLESHOOTING PER B737-800 AMM TASK 49-16-11. REMOVED AND REPLACED APU FUEL CONTROL UNIT IAW AMM 49-31-11 OPS AND LEAK CHECK GOOD GROUND VERIFICATION SUCCESSFUL.