1989 Audi 90 Radiator fan comes on when key is turned

Tiny
AUDI90QUATTRO
  • 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.

Do you
have the same problem?
Yes
No
Sunday, February 22nd, 2009 AT 2:13 PM

5 Replies

Tiny
AUDI90QUATTRO
  • MEMBER

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?

Was this
answer
helpful?
Yes
No
Sunday, February 22nd, 2009 AT 2:35 PM
Tiny
AUDI90QUATTRO
  • MEMBER

Anyone? Someone?

Was this
answer
helpful?
Yes
No
Sunday, February 22nd, 2009 AT 8:59 PM
Tiny
JACK42
  • MEMBER

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.

Was this
answer
helpful?
Yes
No
Monday, February 23rd, 2009 AT 7:43 AM
Tiny
AUDI90QUATTRO
  • MEMBER

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.

Was this
answer
helpful?
Yes
No
Monday, February 23rd, 2009 AT 2:40 PM
Tiny
JACK42
  • MEMBER

I saw that too. Just unplug it to see if it will fix it.I will send you the wiring diagram

Was this
answer
helpful?
Yes
No
Monday, February 23rd, 2009 AT 3:03 PM

Please login or register to post a reply.

Other Fan Stays On Questions