i bought a 2008 s6 with 120k on it damaged in the front, had to replace the rad support condenser and radiator, the cooling fans were intact but there housing was busted, so i just replaced the housing. so now i have it all back together and the fans do not kick on, even if i turn the ac on, but the ac compressor does kick in. my question is does any one know what is required to turn the fans on? both plugs have two big wires and two small wires going to them. i would like to see if i can manuly make them go on before ordering new ones.
Did you check the fuse? There is probably also a relay
I have checked fuses and swapped some relays around with no success maybe im checking the wrong ones? does anyone know what fuses and relays control the cooling fans?
Welcome to AR andy.
Here are a few things to try and think about. There is a chance that depending on how the front end was damaged that your fan controler is bad. You can test the voltage going to the controller but then again there wont be a voltage to the controller all the time.
If you have vag com you should be able to see if there are any codes and also do an output test to run the fans. The fans dont kick on right away just because the AC is on.On the A6 S6 there needs to be a certian temp that gets exceeded.
If you dont have a vag com you can try this.
Unplug the battery and then go upto the passenger side. Pull the rain cover off of the intermiediet fire wall and expose the two ecus that are there. If you unplug both of the ECUs then plug in the battery and key up the car the fans should turn on. If they dont kick on that would be the time to check the voltage to the fan controller.
update
There are two strip fuses under the plastic part the holds the ecus they were both blown
Wow well that would do it. Any chance you can take a picture of the fuses and the exact location. It might help others.
Also you said the car was in a crash but was there anything that would help explain why those fuese were blown. Maybe a wire short after the crash