One problem related to battery has been reported for the 2003 Volkswagen Passat. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Volkswagen Passat based on all problems reported for the 2003 Passat.
Pollen filter and/ or sunroof drains become blocked and water leaks behind battery and into cabin of car. The water then pools under and behind the drivers seat where the convenience module is stored. I am concerned because it caused my car to be unable to start because it is affecting the electrical components of the car. In addition, the pooling under the drivers seat is troubling since it is a hub for interior electrical equipment. The convenience module in my car now has to be replaced.