As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE CREW REPORTED THAT THE LEFT AIR CONDITIONING UNIT CREATED BLUE SMOKE IN THE COCKPIT WHILE RUNNING AT MAXIMUM COOLING WITH VERY LITTLE CONTROL OVER THE COCKPIT AND CABIN TEMPERATURE. MAINTENANCE FOUND THE AFT AIR CYCLE MACHINE FAN TO BE SEIZED. THE AFT ACM WAS REPLACED. DUE TO AN EXCESSIVE OIL LEAK THE FORWARD ACM WAS ALSO REPLACED. OPERATIONAL AND LEAK CHECKS WERE SATISFACTORY. THE AIRCRAFT WAS RETURNED TO SERVICE.