This Preliminary Information communication provides information to the technician for multiple concerns including service engine soon light, reduced power, no crank or start, multiple warning lights on, transmission shifts hard, or the door locks cycle while driving. The transmission control module or engine control module may not communicate with the scan tool. This could be caused by unseated pin or pins in the transmission connector. The technician should inspect the transmission connector X1 terminals by disconnecting it and carefully tugging on each wire to ensure the pins are fully seated. On the Cadillac ATS and CTS only the check the harness securing bracket on the passenger side of the vehicle were the transmission bell housing is attached to the engine block the harness should hang below the securing bracket. The harness should also be checked for chaffing.
