As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE ON THE GROUND, CREW REPORTED CABIN STARTED FILLING UP WITH SMOKE STARTING FROM LAVATORY AREA. SMOKE WAS ALSO NOTED TO BE COMING OUT OF THE EXTERIOR EXHAUST AND INLET PANELS FOR THE AIR CONDITIONING UNIT. MAINTENANCE FOUND THE FREON AC COMPRESSOR MOTOR SHOWING EVIDENCE OF EXCESSIVE OVER HEATING.