I bought a 2007 Volkswagen Passat 2.0 TDI DSG in July 2009. It had done 26,000 miles and is a great car, except for one fault that the Volkswagen dealer cannot fix. The car locks itself when it's not supposed to. It's very sporadic. When unlocking the car with the remote it has locked itself immediately twice. Sometimes when I get into the car, after closing the door, before I get chance to put the key into the ignition it has locked all the doors. I put this question onto the internet and received a reply from a Volkswagen technician in the USA, who said he had only ever seen this problem once before. The problem only used to occur about once a month and was very difficult to solve. They found part of the wiring loom sometimes went to earth in the drivers door causing all the doors to lock. I took this information to the dealer but no problem was found with the loom, but they changed it anyway.

The dealership has always been very helpful. They have had the car six or seven times but have never found the fault. The last time I had a replacement car for four weeks but they still couldn't find the fault. They have changed the sensor that detects if the doors haven't been opened after being unlocked, and other bits and pieces. Any ideas?