Replacement of Battery Causes TCM Damage
A 2003 Volkswagen Passat come into our shop with multiple codes and harsh engagements and was in failsafe mode. The customer said he parked the vehicle and when he started it the next day he noticed the problem. At times the TCM would fail to communicate with the scan tool. When we removed the carpet at the passenger-side floorboard to check the TCM for voltage, we noticed the whole bottom of the floor had about 2 inches of water.