vr6 thermo fans

[dark]

Hey Guys,
Just a question for the vr6 guys here - how long will your thermo fans run after switching off? Mine will run for ages, even if i just switch the ignition on and off! Its not really a problem just wondered why this happens?
P.s I tried searching this (as I'm sure I'm not the first to ask) but the search function as usual failed to deliver!
thanks in advance!

[The_Hawk]

The google search can work better, but then the built in search isn't all that bad either... I used it to find my old thread:

http://www.vwwatercooled.org.au/f47/thermo-fans-running-full-tilt-7162.html

In my case I had an electrician go over it and couldn't work it out so put in a hard on/off switch.

Later (and not mentioned in that thread) when I replaced most of the AC system the problem went away. It seems the high pressure switch in the condensor is linked to the thermo fans (essentially to allow extra cooling for the AC system when it's on).

Have a read through and see if that sounds familiar.

[dark]

hey Aaron,
Your issue sounds different to mine, my fans only run when I turn the ignition off after driving or even if I turn it on and off for 2 seconds, they will then run (after I have locked the car and walked away) for up to 20 - 30 minutes? Seems weird to me but as I said no real bad side so far.
Re the search function I just searched your exact thread title and it still didn't bring it up........also weird.

[Ben J]

does it do it when the engine is cold?

[dark]

yep - I could go down first thing in the morning and start it and turn it off and take the keys out and it will run the thermos for 20 mins.

[The_Hawk]

Mine used to do the after run thing as well.

The cooling system has a bunch of sensors (including the AC pressure sensor) as well as a control module. Are you anywhere near a VW specialist? Worth going to someone who can swap out the sensors one by one to see if they help (I'd start with swapping the control module). The beauty is you don't actually have to install any of the sensors, just plugging them in is enough (since you want to register a low temp anyway and the fans NOT turn on).

[dark]

thanks for the info - i will check it out