Electrical issue?

[BlackVr6ix]

So i'm having a few problems with my VR since i stopped driving it every day. The latest issue is with the thermo fans which appear to have a mind of their own,

For the last few times i've driven her as soon as th key is in the on position the fans come on on high. Even when stone cold! This doesn't really bother me, its when they come on low speed at 2am in the morning and trigger my alarm! Combine this with flattening my battery its getting more than irritating.

I did accidentally get the fan module a little wet a few weeks back and i just hope i didn't kill it. If i can just stop the low speed at 2 i'd be happy!

[The_Hawk]

I had issues with my fan being on 100% all the time when running. I would turn the car on and the fans would come on, then the afterrun low speeds would stay on for what I assume is the default amount of time after the car was off. Mind you they didn't come on at night for fun. (that I know of).

Anyway, we tried substituting a new control module, temp switch, hell even the fan itself to no end.

In the end I had a manual switch put in to turn the high speed off. But then when I finished getting the AC fixed and replaced the pressure switch on the drier/receiver it magically worked properly again, so I have had the switch disconnected. Sadly I have read the wiring diagram for that part of the system waaaay too much.

Did you know the VR6 has 4 different temperature probes??
Off the top of my head:
On the radiator is one sensor, black body which I think runs the thermostat...
There are three on the fron of the engine, blue two pin runs the manual guage (needle) inside, yellow four pin turns on the high speed and afterrun, the last one feeds the ECU.
It's in Bently to an extent, but after much reading I have come to the conclusion that the computer in the VR6 is made from some sort of black magic which defies all logic.

[BlackVr6ix]

I suspect it could be a failed temp sensor as i have been reading the fans come on high as a failsafe in an overtemp or failed sensor situation.

[DVR68U]

yeah ive have my fan module fail before and it left the fans one all night. you could see on the bottom of it that it had melted. if you need one ive got a spare one, since ive gone with out it on my mk2 vr6
cheers brenton

[The_Hawk]

Don't go removing and replacing sensors for the fun of it. The easiest way to test a sensor in this case is to just unplug it and plug the new part in while holding it in your hand.

Basically while it's in your hand it should be reading ambient temp which is more than low enough that the fans shouldn't kick on.

It beats the hell out of draining fluid, pulling something apart, replacing a sensor only to find out it still doesn't work. Trust me.

On the flip side, if your after the black bodied sensor that sits on the radiator, I have one I bought brand new from VW for about $60 (from memory) that I never ended up putting in. PM if your interested and I'm sure we can work something out.