A/C radiator fans not working

[RuZleBiFf]

Hello.

I have an 2004 Audi A3 3-door (8p0), and lately I've been having problems with both of the radiator fans. "Problems" as in not working at all.
The A/C was warm and a garage told me the compressor was dead.
Changed the compressor and refilled the system with gas. Think the A/C is blowing colder now, but only when I'm driving. But the fans are still dead.
I used a multimeter on the contact at the bottom of he fan, and the two big wires have 12v and ground. The blue/red has 12v (through fuse F8 I think) and the yellow/purple wire have something like 2,2v. As far as I know this is the campus-wire and you should use an oscilloscope to check it. But at least, when I turn the ignition on, it pops up to 2,2v.
Had a fried at Audi look at the "cable-map", and he said the fcm is inside the fan on my car, so no use in trying to look for that.

I was at a junkyard and got another fan, but they did not have one with the exact same number. Mine ends with 227M and the new one ends with 227AQ. Still no action.

I'm running out of ideas, so any help is much appreciated!

Best regards
Sindre

 

[dp_motley]

Did you check a heater resistor pack? I had this problem on my old car, 2002 Seat Toledo. I believe it's the same technique as 8P0.

A thing like this (check compatibility) http://www.ebay.co.uk/itm/VW-VOLKSW...OWER-MOTOR-FAN-CONTROL-RESISTOR-/201413139768

 

[RuZleBiFf]

Isn't this only for the fan inside of the car? Or is there another one for the fan-pack behind the radiator?

 

[dp_motley]

Oh, sorry. I should read the OP more careful.

What about a thermostat?

 

[RuZleBiFf]

Might be a thermostat, but i think the fans are supposed to run, as long as the climate and/or AC is on.

 

[RuZleBiFf]

Anybody else got any idea what could be wrong?

 

[RuZleBiFf]

Earth to AC Compressor was broken off. Fixed that, and the fans spun right up.

 

[Jon a4 3.0]

I would say it is the fan units themselves. The main fan has internal controls and also commands the ac fan.
If there is power to the plug that goes to fan it is highly likely it is internal electronics in main fan.
I had same probs with my a3 3.2 , they started staying on at odd times for a while then packed completely, got set from breakers on web.
So long as you look for same number of fan blades, direction of rotation ( theres an arrow on middle of main fan that shows direction) and same diameter and same wiring plugs should be ok.
The pair i got were actually of a later tdi but were exactly same as my old ones.