Slow-reacting heated seats

Hello,
'Recently, my standard seat heating system has been exhibiting the following phenomenon:'
After turning it on, nothing happens initially, but after about 10 minutes, it suddenly becomes warm. The time varies, but the delay is always present! On the passenger side, it works immediately as usual.
Does anyone have any ideas? Does the heating system actually run through the comfort module, or is it separate?

Thank you and best regards.
Werner.

Werner wrote:

... at first, nothing happens, then after about 10 minutes, it suddenly

.

Hello Werner,

Unfortunately, I don't know how the seat heating is electrically implemented.
If it's controlled by a relay, I would check to see if the relay is stuck or has cold solder joints.

Best regards, Rainer.

The strange thing is that it exhibits the exact same behavior every time I start the car. I tested it again yesterday. After starting the car, the seat was cold and only became warm after 15 minutes. Then, when I briefly turned the ignition off and on, the seat became cold again.

Werner.

Does anyone happen to have a detailed wiring diagram (for a Passat Variant 98, engine code AFN) that includes the seat heating system?

Regards,
Werner.

Hello Werner,

Maybe this will help:
I installed a seat heater from Conrad myself. It's the type that you have to install directly into the seats. It has some kind of thermal shut-off: when it reaches a certain temperature, it turns off, cools down slightly, and then starts heating again.
I think a protective circuit like that should have the same features as the one from Volkswagen. Maybe that's where the problem lies!

Best regards.
David.

In older models, there were sometimes problems with the regulator itself (in the Golf, everything goes through a comfort module, and all the electronics are located in the switch).
Perhaps you could swap it out first. Otherwise, the only other thing I can think of is a nearly broken cable; unfortunately, heating mats tend to wear out quite quickly.

Best regards, Juan.

I took a look at the relay collection earlier and found what I was looking for. A control module in the box on the lower right contains the electronics for both seat heaters... and sure enough, one of the relays had a burnt contact. Cleaning it helped only a little (enough to know that it's the contact), so I will probably have to replace the relay. Thanks for the tips...

Regards,
Werner.