AC Blower stopped working

[nibbles]

So after my recent venture to VW for an issue with the supercharger (which you can read about here) I've come up with another problem...

33˚ this afternoon and about half way home I decided it was time to turn on the air con (dual zone climate control version). Nothing happened. The fan didn't start. I tried off and on, etc and still nothing. The air con compressor will kick in and produce cold air but without the blower it doesn't do much other than cool the vents.

I had a bit of a look this evening and checked all the fuses I could find (side panel and under the bonnet) and they all checked out ok with the multimeter. I then proceeded to try and find the relay I could hear clicking in the passenger footwell by removing that carpet trim piece but I can't see much.

Putting the multimeter on the wires pictured below which appear to go inside the blower (with it connected) gave 2.5v momentarily when turning it on but then it'd go back to zero.



The below has 12v constant even with the ignition off across the Red & Brown and with it disconnected the clicking stops which leads me to believe this is going to the relay.




My question is: does it sound like it could be the relay causing the issue or would it more likely be the blower itself, possibly even something stuck in the top of it from during the service (I hadn't had it on since then)?

Can anyone provide me with more info on actually removing the blower unit or accessing the top side so that I can check there's nothing stuck in it and test it the relay a little more?

[Umai Naa!!]

I have seen the fans go bang in the past.

You can remove/test/replace the whole bottom half of the blower fan unit, including the motor, by removing the series of screws that hold it in. As per diagram, item 1:

[nibbles]

Annnnnnnd it's sorted!

For anyone interested it was the relay (I assume you'd call it that though it's a little more complex than a normal one) on the bottom side of the blower in the passenger footwell, the thing that wires connect into in the photo above.

It took about 1hr and 10 minutes to remove it, repair it and reassemble it with the blower still in place. All I had to do was remove the 2 6mm hex head screws and drop it out the bottom.

On the bench I was able to remove the circuit board from the plastic enclosure and clean it with CRC Electronics contact cleaner, there wasn't any visibly damaged components though there was a little bit of what looked like moisture around on one corners which the cleaner looks to have removed.

Back in the car I tested it was working before reassembling. Just have to hope now it doesn't pack it in again.

[hoi polloi]

Annnnnnnd it's sorted!

Glad to hear.. I found the blower motor in my car had a very stiff lower bearing... It seems to be due the orientation of the motor itself (vertical) that seems to allow crud to collect in the base... Cleaned it out and lubed the bearings with a touch of light oil...

- Anthony

[Snail Style]

It's a resistor pack, not a relay. That sets how your fan speed operates. Have seen a few of them crap out and need replacing.

[nibbles]

It's a resistor pack, not a relay. That sets how your fan speed operates. Have seen a few of them crap out and need replacing.

I should've grabbed a photo of it while I had it out, it's definitely not a resistor pack like in the mk5 (below). It had a great big coil across the middle, a couple of capacitors and a handful of integrated circuits all combined on one PCB. And it's got the well defined 'click' like you'd hear on a relay.

EDIT: I stand corrected. Bloody complicated just to control a fan if you ask me. It's one of these: New Audi VW Blower Motor Resistor A3 Quattro Q7 GTI OE 3C0 907 521F | eBay

[Snail Style]

It's abit more. Complicated than just a resistor pack like in older model cars. It is also considered a control module, i believe it will cut supply to the blower if it begins to draw too much current, etc.