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Model specific boards => Golf mk3 => Topic started by: Gungemyster on 04 August 2010, 12:02

Title: Fan sensor
Post by: Gungemyster on 04 August 2010, 12:02
I have changed the thermostat on the Mk3 GTI 2ltr 8v (which in its self was difficult let alone bleeding the system afterwards!!).
For some reason now though when its parked up the fan comes on and stays on.
I initially though rad sensor but I have replaced this and still the same, it just comes on and stays on.
Is there a second sensor somewhere or has anyone else had this problem??
The car hasnt been started in days now, but if I connect the fan up even without connecting it to the sensor, it just comes on?
Title: Re: Fan sensor
Post by: rubjonny on 04 August 2010, 12:28
if it does it even with rad sensor unplugged, its a problem with the fan control unit or its the rad fan after-run sensor. you'll find it near the inlet manifold on a bracket, its single pin with a yellow collar. wire is brown/black or brown and may have a black outer sheath

pic:
(http://vwtech.no-ip.info/images/golf/afterrun.jpg)
Title: Re: Fan sensor
Post by: Gungemyster on 04 August 2010, 15:17
Awesome, cheers buddy, I will take a look at it tonight to see if I have knocked it off whilst doing the thermostat and post to let you know.
Title: Re: Fan sensor
Post by: Gungemyster on 07 August 2010, 09:01
Im really struggling with this guys, I just cant find a second sensor for the after run.

With out the engine being on or hot, with the rad fan discoonected the rad fan still kicks in and runs.

2ltr Mk3 8v engine.

HELP ME PLKEASE!!!!!!!!!!!
Title: Re: Fan sensor
Post by: Maltloaf on 11 August 2010, 12:01
if it does it even with rad sensor unplugged, its a problem with the fan control unit or its the rad fan after-run sensor. you'll find it near the inlet manifold on a bracket, its single pin with a yellow collar. wire is brown/black or brown and may have a black outer sheath

pic:
(http://vwtech.no-ip.info/images/golf/afterrun.jpg)

Would these faults appear on VAGCOM, or is it simply a case of unplugging it at testing the old fashioned way?  :wink:
Title: Re: Fan sensor
Post by: Gungemyster on 11 August 2010, 17:16
I think I have sussed it.  Its not the same as this in the picture.  I found a relay/switch under the expansion bottle which had damp in it.  I removed it to find it was full of water (must have happened when I was bleeding the system.  I have later found out that this is the fan relay switch.
I have bought one off ebay which arrived today, so I will try it out tonight and post back up on here.

Fingers crossed!!