As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU AUTO SHUT DOWN DUE TO LOSS OF OIL PRESSURE. SHOP FINDINGS REVEALED DRIVEN COMPRESSOR FRONT CARBON SEAL ASSEMBLY LEAKED. THE INTERNAL LIP SEAL WAS PINCHED BY THE WAVE WASHER AND EXCESSIVE ABRAIDABLE MATERIAL IMPEEDED CARBON TRAVEL. THE DRIVEN COMPRESSOR WAS REMOVED AND OVERHAULED. THE CARBON SEAL ASSEMBLY IS REPLACED DURING DRIVEN COMPRESSOR ASSEMBLY.