Automatic Transmission Control Module problems of the 2005 Chevrolet Silverado 2500

The contact owns a 2005 Chevrolet Silverado 2500hd. The contact started the vehicle and shifted the gear selector into the "drive" position; however, the park indicator remained illuminated for ten seconds. In addition, the automatic door locks became inoperative and failed to lock when the gear was placed in "drive". The doors would lock only manually. Also, the rear back up lights would not function. The vehicle was taken to the dealer where the tcm transmission module was replaced. The vehicle operated normally after the repair. The failure mileage was approximately 24,416.