Conor Curtin

Hi, my 09 A3 wont kick on any of the fans-both blower and rad. I did a scan in VCDS and found fault 01273 - Fresh Air Blower (V2) 003 - Mechanical Failure. I would have to assume that the problem is the actual blower fan, but I don't know. I don't receive any errors from the rad fans. I have put power straight to the rad fans and they do turn on. Any ideas of what to check now?

habbyguy

Not familiar with your year, but have you checked the appropriate fuses and relays?

FWIW, here's a snip from my manual (for an '06) that shows the vagueness of how Audi seems to do things... ;-)

Conor Curtin

I've checked all of the fuses and they look fine but i dont have a multimeter to check continuity. I did have a terminal 30 error that has since cleared up, and i swapped relays KL30 and HORN and that didnt do anything. How would i go about testing these relays properly?

habbyguy

You really need a multimeter, but could use a test light in a pinch. Just find out if the relay coil is getting power when expected, and see if there is power to the "input" side of the relay (one of the - usually - three "non-coil" connections should be hot with the key on. If you swapped the horn relay (assuming it was the same as the fan relay), and the horn worked before and after, you can pretty much rule out a bad relay.

Just reading through the Audi explanation of how they turn on fans makes my head hurt, and I'm a techie... it seems that they just wire every other car differently "just for fun"... ;-)

Conor Curtin

The horn and kl30 relays have the same part number on my car so i figure that probably isnt the problem. I will give them a test anyway tomorrow just for a sanity check.

Conor Curtin

I haven't had a chance to test the relays, but i went through the fuse block inside the car and all of the fuses for the blower and hvac system are receiving power when the key is in the on position

habbyguy

I'd suggest that you look up the pin-out diagram for that relay, so you know which pins are which. Then do the checks I suggested in my previous post, making sure that you're getting the proper voltage to (at least) two of the socket connections (for the coil and the power "input" to the relay).

Conor Curtin

I just tested relay KL30 and it is getting some form of power to what I think is pin one. Its the first pin on the relay. Everything else is not getting power. I jumped a bunch of steps and pulled the blower motor and it feels basically seized. The fan doesn't want to spin much at all. I would have to guess that is at least part of the problem

habbyguy

I thought the fans both spun up fine with 12 volts applied directly (if not, then yeah, no doubt that a bad fan will cause the fan not to come on). ;-)

There should be two pins on the fan relay getting power, as long as the car is turned on and in the mode that should have the fans running (like with the A/C on). One would be the power to the switched contact (the one that's routed to the fan with the relay on), and the other to the positive side of the relay coil. I really don't know what pin is what on your relay though.. (pin numbers can be pretty random).

Conor Curtin

Ok thats good to know. To my understanding, KL30 is a general relay, but i don't know what or if there is a more specific fan only relay somewhere else. Do you know where i can find a wiring diagram so that i can see where the relay is also supposed to be getting power from?