Author Topic: fans not cutting in after 90 degrees  (Read 1126 times)

Offline matping

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fans not cutting in after 90 degrees
« on: 09 April 2010, 14:18 »
any ideas anyone ?? could it be the thermastat  the cars hed new rad and new rad temp switch that goes into the rad

it gets to the point where the water starts boiling out the expansion bottle
« Last Edit: 09 April 2010, 14:22 by matping »

Offline Purely VAG

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Re: fans not cutting in after 90 degrees
« Reply #1 on: 09 April 2010, 14:24 »
Thermostat is what allows water to pass at certain pressure. IE your car would run too hot, or too cold.

Your fans should kick in regardless.

I use 2 pieces of wire from battery and give fan motor a direct feed to see if it spins. Try that and report back.

Live to Live, Earth to Earth.

You can check it with a multimeter to see if its receiving a Live, but requires warming the car up to the point where it would kick in/then you dont want to turn off but at same time you dont want car to overheat hence method i use above.

✉ Jrd@PurelyVAG.co.uk // www.PurelyVAG.co.uk

Offline Mr_Orange

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Re: fans not cutting in after 90 degrees
« Reply #2 on: 09 April 2010, 14:28 »
Beat me to it!   :grin:

Nowt to do with thermostat if its getting up to temp OK.

Has it over-heated?  Car has got to get very warm for them to come on.  They are very quiet too.  

Have you got air-con?  Pop it on and go look if both fans come on.  There's plenty of info on line about them playing up, but I think its mainly related to lack of fans with aircon.

There is also a test you can do with a short length of chunky (well insulated) wire, you remove the plug from the rad fan switch and bridge certain plug contacts, this verifies the fans work if the fan switch tells them to.

Take a search about on google?  :undecided:


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Offline matping

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Re: fans not cutting in after 90 degrees
« Reply #3 on: 09 April 2010, 14:32 »
ive put a direct feed to the fan and yea it spins  i found when the car was hot  i tried the aircon by pressing the switch in the car and the fans kicked in  but only when the temp guage was over 90 if i hadent of pressed the switch the fans wouldent of done anything  !

Offline Mr_Orange

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