Passenger Door Electric Failure: Common Causes & Fixes

Hello.
"In my Passat 1.9 TDI (manufactured in December 1998), the electrical system occasionally fails, meaning that features like the mirror controls, central locking, and window lifters stop working, except for the puddle light."
- Could the problem be with the control unit itself, or more likely with its wiring?
- Where is the control unit located?

Thank you very much for your help.

First, check the connection between the car body and the door. There might be contact problems there, and if it only happens occasionally, the likelihood of a loose connection is quite high, especially since the door light turns on when the door is opened.

The contact between the door and the body is fine; it needs to connect to the control unit, but I'm not sure where that is located.

Thank you for your help; the cables in the door seal were broken. I soldered everything back together and insulated it, and now everything is working again!

"You're welcome, as described, it's a typical issue with VW cars. It's a shame, really. Thanks for the feedback."