Two problems related to battery cable have been reported for the 2012 Volkswagen Passat. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2012 Volkswagen Passat based on all problems reported for the 2012 Passat.
This car is built with reversed color coded battery cables without proper, easily identifiable polarity identification. The factory battery has conventional markings, red +, black -, however the black cable is designed to go on the "+" terminal and the red cable is designed to go on the "-" terminal on this model. There are no obvious polarity markings on the cables. If one looks very carefully you can find a tiny - stamp on the red cable terminal and the tiny + stamp is half covered by insulation and hidden on the black cable terminal.
This car is built with reversed color coded battery cables without proper, easily identifiable polarity identification. The factory battery has conventional markings, red +, black -, however the black cable is designed to go on the "+" terminal and the red cable is designed to go on the "-" terminal on this model. There are no obvious polarity markings on the cables. If one looks very carefully you can find a tiny - stamp on the red cable terminal and the tiny + stamp is half covered by insulation and hidden on the black cable terminal. The battery terminals are of slightly different diameters to guide you to the proper installation but the diameter difference is not large and is easily adjusted with a screwdriver which I have had to adjust to fit on cables that were not improperly reversed in the past. Not noticing the reversed color coded cables prior to replacing the battery I hooked up a new vw oem replacement battery with reversed polarity as a result of the improper/reversed battery cable color codes. The cables were not tightend, just placed on the terminals at which point the horn sounded and would not go off at which point I removed the cables and looked very closely for markings indicating that I might have hooked them up improperly and noticed the aforementioned very hard to find tiny hidden stampings on the terminals revealing that I had hooked up the battery with reverse polarity. This resulted in $3000 of electrical damage to the car - and almost caused a fire, melting some of the harness and electronic control modules. Additionally 2 of the 3 protective fusible links designed to protect this circuitry melted together short circuit (instead of fusing open circuit) not protecting anything. This is a very dangerous multiple defect design that has the potential to cause injury and fire in addition to extensive damage and costly repairs.