1989 Audi 90 Radiator fan comes on when key is turned

1989 AUDI 90
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AUDI90QUATTRO
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Engine Cooling problem
1989 Audi 90 All Wheel Drive Manual

Just yesturday my fan started running full time when the key is turned on ( car doesint have to be running ). FYI: the fan is running at high speed, so Im not sure if maybe the high speed switch failed or if 1 relay does it all.

Any help would be great, I dont have a manual so I have no clue where the fan relays are.
Feb 22, 2009 at 2:13 PM
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AUDI90QUATTRO
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I feel like an idiot, all the fuse box info is on the cover... anyways, I pulled all the fan relays and it still kept running when the key is turned. I did pull fuse #20 ( 1st speed, cooling fan ) and it turned off, but I cant run without a fan. So are there any other fan relays I should look at?
Feb 22, 2009 at 2:35 PM
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AUDI90QUATTRO
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Anyone? Someone?
Feb 22, 2009 at 8:59 PM
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2CARPRO JACK
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There is a cooling fan "after run thermo switch" and "controller" These look like the only way thefan could run with ehrelays removed.I included the wiring diagram , you may need to open it in Microsoft Photo editor to enlarge it.If you cant send me your email and I will send it to you that way.The controller is in thesame fuse block as the relays. See if the red/green wire out of it is always hot, that looks like it supplies power to fuse 20.
Feb 23, 2009 at 7:43 AM
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AUDI90QUATTRO
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Thank you.. here is my email: [email protected]

I did some more research and I found that another cause may be the temp sensor/fan switch thats on the radiator, what do you think? I would just go and buy one but at $50 a pop thats a pricy way to do trial & error testing.
Feb 23, 2009 at 2:40 PM
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2CARPRO JACK
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I saw that too.just unplug it to see if it will fix it.I will send you the wiring diagram
Feb 23, 2009 at 3:03 PM