As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT THE GATE WITH APU RUNNING THE CABIN STARTED FILLING WITH SMOKE. SHORTLY FOLLOWED BY APU AUTO SHUTDOWN. C/W GVI OF APU. OIL IS AT SERVICEABLE LEVEL. NO EVIDENCE OF OIL LEAKAGE OR ANY OTHER DEFECTS FOUND. C/W MCN 62172-01 ISSUE NR 2 AND AIR CONTAMINATION CHECKLIST. C/W AMM TASK 21-00-00-160-801 FOR ECS SYS PURGE USING ACFT ENGINES. OIL SMELL WENT AWAY AND DID NOT RETURN. APU PLACED ON MEL. MEL CLEARED BY REPLACING APU. RETURNED TO SERVICE.