JoeBlowAudi

2009 Q5 3.2 - 53,000 miles

Four days ago, I started having problems with the HVAC fan. After driving for about 6 hours, stopped to get gas, and when I started back up, the A/C was on, I could feel some cold when touching the vents, but there was no air movement. After about 30 mins, the blower started moving air again.

Here's what I experienced:

• With A/C on, blower worked sporadically, sometimes right away after starting the vehicle, sometimes 15-30 minutes after
• Changing the climate control temp to hot or cold had no effect on the fan
• When not blowing, changing the fan speed had no effect
• When blowing, didn't get much air movement without turning the speed to 12, and even then it wasn't blowing hard
• When blowing, with the fan speed set on 12, there was a lot of fan noise from behind the glove box, but not much air movement from the vents
• During 14 hours of driving yesterday, everything seemed normal for the first 10 hours, for the last 4 hours I couldn't get any airflow

All of the fuses I could find related to the blower and climate control look fine. I've read some posts about bad blower motors and controllers.

Is the controller the 'Blower Motor Resistor'?

Is there anything else I should be looking at besides the blower motor and resistor?

Is it possible to test voltage to the blower motor, and if it is getting voltage, rule out the resistor as the problem?

Prices for the motor look to be around $160 and the resistor is about $330. If I don't need to replace both, I'd rather not.

What are your thoughts?

Thanks for any help!

spijun

Maybe you have a problem with the air conditioner filter
Try to remove the filter for the air conditioner, sometimes due to humidity can be clogged.
Test how it works without filters

JoeBlowAudi

Are you talking about the cabin filter?

spijun

Exactly

Because of this:

vutekho

I had this exact problem for the first time yesterday, and still today.

What I done, was turn the AC off, but leave the fan on. Then, I manually adjust the fan to different speed, and the fan works properly. While the fan is running full blast or any other speed, I turn the AC back on, and it blows cold air at whatever speed you manually set it at. But, when I put it back into AUTO mode, it'll stop readjusting fan speed automatically and lose control of fan speed with AC on.

So the blower/fan works fine. Something else ia causing a conflict between the fan speed with the AC and AUTO mode. Or I could bw completely off.

To replicate the problem, I'll have to drive for about 2hrs with a new cabin filter or no filter at all.

Q5 Bob

Where is the cabin filter located? In the manual they talk about replacing it, but don't have any DIY information. Tks.

JoeBlowAudi

In the top of the passenger footwell toward the back, there's a foam cover held in place by three plastic thumb screws. Take out those screws and pull the foam piece down. You'll see a hard white plastic piece about 2" x 10". Slide that white plastic cover length wise to release it and set it aside. The cabin filter is in there. Simply pull it out.

Q5 Bob

Good info. Thanks...

dscline

I know it may not be much help, but these are the exact symptoms I had in my A4, and they replaced BOTH tbe motor & motor controller. At least that's what the ticket said.

JoeBlowAudi

I can't get it to fail tonight.

I pulled the filter it's only slightly dirty. With the filter in or out, I don't notice any difference in airflow at the vents.