As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PHX - INFLIGHT SFO-MIA. CREW REPORTED AUXILIARY POWER UNIT OIL QUANTITY ON EICAS STATUS THEN APU FAULT. LEFT ENGINE GENERATOR ALREADY ON PLACARD. FLIGHT DIVERTED PHX LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED O-RING ON BLANKING PLATE ON BOTTOM OF APU GEARBOX. SYSTEM GROUND CHECK NORMAL OPERATION.