Mechanics

RADIATOR FAN COMES ON WHEN KEY IS TURNED

1989 Audi 90

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.
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Audi90quattro
February 22, 2009.




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?
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Tiny
Audi90quattro
Feb 22, 2009.
Anyone? Someone?

Tiny
Audi90quattro
Feb 22, 2009.
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.

Tiny
Jack42
Feb 23, 2009.
Thank you. Here is my email: paul_g@go-geartactical. Com

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.

Tiny
Audi90quattro
Feb 23, 2009.
I saw that too. Just unplug it to see if it will fix it.I will send you the wiring diagram

Tiny
Jack42
Feb 23, 2009.

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