Long ago I ('93 TT) disconnected and removed a relay mounted on the wall to the left of the driver's left foot to stop the passenger side door from unlocking when I unlocked the driver side door. I think I had to remove a plastic cover and peel back some foam pad to get to the relay. I didn't like the passenger side door unlocking when I was the only one getting in the car for security reasons and also due to the unnecessary wear and tear on the passenger side door lock mechanisms and motor.