Hi , my son has a MK 3 Golf and I have a Mk4. His windows are always screwing up. The wife unlocked his car and the back window went down but wouldn'tgo up. There was a problem with the ignition starter switch which we fixed with a momentary button switch. Could it be related or is it relays. The brakes are also US, it is a diesel. I suspect the vac servo pump or the Servo PAS. Any thoughts greatly appreceated.