The definitive VR6 cooling guide

[Walesy 0]

Sounds like it to me!

 

Just looking at Kevs guage, I noticed these the other day - http://www.swgmotorsport.com/asps/ShowD ... asp?id=227 - shame they don't do one for the rado!

[Toad 0]

Ok, noticed that the fans come on EVERYTIME i turn engine off after a drive. Now i know they're supposed to come on sometimes but not everytime. Would this be a knackered switch in the radiator?

 

No, I believe the after run fan is picked up off another sensor. Either Yellow, or Black.

[Critical_Mass 10]

Ok, noticed that the fans come on EVERYTIME i turn engine off after a drive. Now i know they're supposed to come on sometimes but not everytime. Would this be a knackered switch in the radiator?

 

No, I believe the after run fan is picked up off another sensor. Either Yellow, or Black.

 

I thought this, just changed the yellow one (which is now black) to fix the gauge reading. The fan never used to come on before changing this, now it will come on each time the ignition is switched off, though it seems only once the car is up to temp.

 

So if that controls the after run fans, then what does the radiator switch do?

[Kevin Bacon 5]

Just looking at Kevs guage, I noticed these the other day - http://www.swgmotorsport.com/asps/ShowD ... asp?id=227 - shame they don't do one for the rado!

 

Indeed, but you can get OBD port software monitoring for the iphone / touch though :D - http://www.plxkiwi.com/kiwiwifi/software.html

 

I thought this, just changed the yellow one (which is now black) to fix the gauge reading. The fan never used to come on before changing this, now it will come on each time the ignition is switched off, though it seems only once the car is up to temp.

 

Yes that's normal. If you turn the car off and the water temp is around 90 degrees, the fans will stay on. If the water is colder, they won't! :D

 

I really have no idea why the VR6 coolant system causes so much confusion and panic!! All the info you need is in this thread :D

[vornwend 0]

 

Indeed, but you can get OBD port software monitoring for the iphone / touch though :D - http://www.plxkiwi.com/kiwiwifi/software.html

 

 

Its a shame the Wi-Fi device is $150 :shock: Anybody know if you can get a cheaper alternative?

[Kevin Bacon 5]

I think that system is unique at the moment. Other companies will follow suit eventually and bring the prices down.

 

I don't think £93 is too horrendous, not when you compare to the price of a genuine VAG-COM lead!

[Critical_Mass 10]

Just looking at Kevs guage, I noticed these the other day - http://www.swgmotorsport.com/asps/ShowD ... asp?id=227 - shame they don't do one for the rado!

 

Indeed, but you can get OBD port software monitoring for the iphone / touch though :D - http://www.plxkiwi.com/kiwiwifi/software.html

 

I thought this, just changed the yellow one (which is now black) to fix the gauge reading. The fan never used to come on before changing this, now it will come on each time the ignition is switched off, though it seems only once the car is up to temp.

 

Yes that's normal. If you turn the car off and the water temp is around 90 degrees, the fans will stay on. If the water is colder, they won't! :D

 

I really have no idea why the VR6 coolant system causes so much confusion and panic!! All the info you need is in this thread :D

 

Ah but sometimes they come on for say 5 seconds then go off and come back on again :scratch:

 

The VR cooling system has always confused me :lol:

[Critical_Mass 10]

Can i be a pain and ask another question? :lol:

 

Can you tell me what the difference between the fan control switch in the radiator and the yellow temp sender that controls the fans? Why are there 2 sensors that control the fans. I unplugged the switch in the radiator today to see if the fans still came on and they did. :scratch:

[Critical_Mass 10]

Anyone shed some light on this for me?

[Kevin Bacon 5]

Can i be a pain and ask another question? :lol:

 

Can you tell me what the difference between the fan control switch in the radiator and the yellow temp sender that controls the fans? Why are there 2 sensors that control the fans. I unplugged the switch in the radiator today to see if the fans still came on and they did. :scratch:

 

There are 3 temp triggers actually :lol:

 

As I say, it's all in this thread, but here it is.....AGAIN!!! :lol:

 

Rad switch - Red/white wire = Fan speed 1 ~ 90 deg

Rad Switch - Red/Black wire = Fan speed 2 ~ 100 deg

Black sender (stat housing) = Fan speed 3 ~ 120 deg

 

The Yellow sender is for the dash gauge and the electric water pump.....

 

Now how is that complicated?! :scratch: :D

[Kevin Bacon 5]

P.S If your fans came on with the rad switch unplugged, that points to a problem with the fan control box on the nearside turret.

 

He is the Daddy of the fans and controls all the speeds and the electric water pump.....

 

A new fan controller is £100+VAT

[Critical_Mass 10]

:oops: Cheers. :lol:

 

It didnt say anything about the rad switch on the first post just how to test it :lol:

 

Anyway to test the fan control unit?

 

 

Thanks again. :D

[Toad 0]

Anyway to test the fan control unit?

 

Take it off and shake it. If it rattles it's a bit broken, but repairable. :tongue:

[robrado974 1]

have read through thread,as i have a few probs.just before me vr was taken off the road for respray it overheated ,its since been serviced and we replaced thermostat,but when we left car running to warm oil up before changing the fans were cutting in just above or around 70d mark ?,is this due to the crusty plugs that were mentioned? or is this ok i cant take the c for a run till i get it back ,was a bit worried bout the 120 mile trip back to my house when me c is ready thanks rob

[Critical_Mass 10]

have read through thread,as i have a few probs.just before me vr was taken off the road for respray it overheated ,its since been serviced and we replaced thermostat,but when we left car running to warm oil up before changing the fans were cutting in just above or around 70d mark ?,is this due to the crusty plugs that were mentioned? or is this ok i cant take the c for a run till i get it back ,was a bit worried bout the 120 mile trip back to my house when me c is ready thanks rob

 

Could be. If the yellow temp sender is crusty it could be under reading, hence the gauge reading. I had this issue on mine and the gauge works fine now. The sensor was only £10.

[robrado974 1]

thanks alot i will get one on order :salute:

[jpowell79 0]

Fans check

1. Take the plug off the rad sender

2. Take the plug off the black temp sender in the stat housing.

3. Switch ignition on.

 

In the rad sensor plug - red wire is stage 1, thin red/black is stage 2. The other wire is the common connection. Bridge each of the two wires in turn across the common wire and see if both speeds come on. If they do, good.

 

4. Bridge the black plug with a paper clip or something, does stage 3 come on? Sounds uber loud!

 

So that's the fan test done. Tick it off as outruled.

 

Can someone help me with this!!

 

I'm struggling with which plug the rad sender plug is! :cuckoo: The only traingle-shaped plug I can see is the one on the right-hand side of the engine above and to the right of where the leads go in the coil pack? Tried bridging the plug with a paper clip and got nothing. Anyone got a picture of this plug so I can see exactly where it is?

 

Also, I tried bridging the plug in the black plug, and nothing again....which is weird because I know my stage 3 fan works, as it kicks in at around 115 degrees (it's stage one and two I'm having issues with!)

 

When you say turn the ignition, you don't mean I have to actually start the engine do you? The reason I'm asking is because my coil pack and thermostat is currently off the car!

 

God I'm so rubbish around cars!! :help: :help: :help:

[aide 0]

I'm struggling with which plug the rad sender plug is!

 

if it's stage 1 & 2 problems you realy should try the radiator sender first, this connector can be bridged in similar fashion, its mentioned in the first post

 

standing in front of bonnet, the rad sender is on the right hand and engine bay side of the radiator about half way up near the battery, it may not be triangle shaped, depends upon your car age, mine was a pain to remove due to wires in the way and fat fingers

 

oh yeh, you'd be better using wire than a paper clip, preferably one end with a spade connector to ensure good connection!

[jpowell79 0]

ok I am so confused with this.....I've found the correct connecter....just near the bottom of the battery....but no matter what I try bridging, I get nothing......

 

but asisde from then, even when I bridge the two points in the black tem sender, the stage 3 fan does not come on?????? but yet I know the stage 3 fan works, because when the car gets up to around 115degrees it comes on....so why is it not working when I bridge the two connectors?

 

All I get is a weird clicking noise from the rad controller box near the coolant bottle? makes no sense to me :(

[aide 0]

well it sounds like you've diagnosed the fault already, a faulty relay in the fan control unit, you may need a replacement, about £20 to £25k for a second hand unit.

[jpowell79 0]

well it sounds like you've diagnosed the fault already, a faulty relay in the fan control unit, you may need a replacement, about £20 to £25k for a second hand unit.

 

but surely my stage 3 fan wouldn't come on at all if I had a faulty controller? :scratch:

[aide 0]

i'll be honest i don't know the detailed workings of the controller, but i've had the lid of my controller before and there's maybe four or five relays which i'd assume all switch a dedicated fan speed, or contribute towards a speed, e.g. relay 1 switches speed one, relay 1 & 2 both contribute to speed 2, relay 3 is dedictaed speed three, relay 4 is switched by the ECU/ air con unit etc

 

have you tried VAGCOM to diagnose any fault codes?

[jpowell79 0]

i'll be honest i don't know the detailed workings of the controller, but i've had the lid of my controller before and there's maybe four or five relays which i'd assume all switch a dedicated fan speed, or contribute towards a speed, e.g. relay 1 switches speed one, relay 1 & 2 both contribute to speed 2, relay 3 is dedictaed speed three, relay 4 is switched by the ECU/ air con unit etc

 

have you tried VAGCOM to diagnose any fault codes?

 

No still waiting for postie to deliver my ODB cable.....hopefully it might turn up tomorrow or staturday morning :)

 

Will take off the controller and have a look inside that as well... I assume it's self explanitory getting the thing off?

[Kevin Bacon 5]

ok I am so confused with this.....I've found the correct connecter....just near the bottom of the battery....but no matter what I try bridging, I get nothing......

 

but asisde from then, even when I bridge the two points in the black tem sender, the stage 3 fan does not come on?????? but yet I know the stage 3 fan works, because when the car gets up to around 115degrees it comes on....so why is it not working when I bridge the two connectors?

 

All I get is a weird clicking noise from the rad controller box near the coolant bottle? makes no sense to me :(

 

Best to conduct these tests with the engine running because speed 3 draws massive current. Might explain the clicking from the controller? Certainly the ignition must be on otherwise speeds 2 and 3 won't work. Only speed 1 is autonomous of the controller with a permanent live connection.

[jpowell79 0]

Well I bought meself a soldering iron at lunchtime, and I've got the fan controller off the car....any idea how I open the thing? :scratch: :scratch: