Webasto Heater Remote Control: Retrofit Guide

Hello everyone in the forum!

I have a Golf IV (built in May 2002) with a 1.9 TDI ARL engine that I use as my winter car, and it already has a Webasto auxiliary heater installed by the original owner.

This one works perfectly, however, so far I can only start it using the built-in clock (Type 1533, oval), which is a problem. I work in a hospital, and it's often not possible to plan exactly when you will be able to leave, down to the minute...

Therefore, it would be worth considering retrofitting a remote control, or even better, enabling control via an app.

Okay, here are my problems/questions:

Unfortunately, I can't say exactly what type of heating system is installed in my car, but I'm sure it's older than 8 years.

Furthermore, I already have a diagnostic adapter, and I thought I could use it to determine the model designation... but so far, I haven't been successful; I can't find a clear naming convention. Communication with the control unit works when I select the device type "Thermo Top C, E, Commercial, P, C/Z MB/DC"...

Can I upgrade any heating system, or is it only possible with certain models or production years?

Is there a way to determine this without disassembling the vehicle or removing the bumper?


Thank you very much, and best regards.

Alex