One problem related to windshield has been reported for the 2004 Volkswagen Passat. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Volkswagen Passat based on all problems reported for the 2004 Passat.
In April 2008 my 2004 vw Passat spontaneously developed a crack, gradually lengthening, in the windshield. I replaced it with an original equipment windshield, and now, in March 2009, the windshield has again spontaneously developed a lengthening crack. In neither case was there any chip or "ding" or anything suggesting any impact of anything into the windshield.