bud4ya

I have a 2001 A6 2.7T and I am wondering if it is normal for the fan it sounds like running all the time when I have the heat on. You can hear the fan running constantly when heat blower is on. When I shut the heat off it shuts off. Hope this is not a dumb question. I just don’t hear a fan constantly running in my other cars when the climate is on.

Thank You

RMsALFA

If you're in AUTO climate control when you have the heat on, it may also be turning on the A/C. If your aux fan (the one in front of the rad) is running, sounding like a air-raid siren, you possibly have a bad fan control module.

Disable the A/C and see if the fan (and noise) stops.

bud4ya

Thank you. I do not have the auto button on I just manually adjust the fan speed and temp by hand. I thought I noticed when I hit the econ button on (lite up) the fan went off. It does not sound bad the fan just constantely runs. When I hit the off button with no heat it goes off. Just does not seem like it should constantely run unless I am doing something wrong.

I will have to try the econ button and see if the fan truley shuts off when I hit that. If it does not really sure what that means either

meternerd

Seems like my fan runs only when the A/C is on, such as in auto and defrost. Econ doesn't cause mine to run unless the engine is hot. But maybe I just never paid attention. Mine is pretty quiet and I can't hear it running from inside the car.

bud4ya

That seems to be the same as mine when econ button is lit up red no fan running. I will have to look at the book again on the settings. What I am wondering is if the econ light is not lit up if the AC compressor is on. When the econ button is lit up red I wonder if that means AC is off. It is in the book I just forget what it said it has been so long.

I do not have the book with me today does anyone know off the top of their head if the econ button is NOT lit up red if that means the AC is on? And or when it is lit up red if the AC is off?

RMsALFA

If the ECON button is pushed (red light on) the A/C should never come on - that's why the refer to it as "econ"

There are TWO fans - one in front and one behind the radiator. Which one(s) is(are) running ?

clancy

When the econ button is lit up red I wonder if that means AC is off. YES
I do not have the book with me today does anyone know off the top of their head if the econ button is NOT lit up red if that means the AC is on? YES And or when it is lit up red if the AC is off? YES

bud4ya

Guys thank you. I am willing to bet that is the compressor running as I have been running the car with the AC on as the Econ button was not lit up red when I hear the fan noise. I did notice when I turn off the AC, red light on the econ button is lit up the fan noise goes away.

I will listen closer and see where the fan noise is coming from when the AC is turned on.

I wondered why my mileage has gone from around 21 to 19

RMsALFA

I believe the fans work like this:

The fan behind the radiator runs when the coolant temp sensor "says" it should. The forward mounted fan runs when the A/C is enabled. How fast it runs is dependent on various sensor inputs. There is a module mounted on the rear of the front cowling assembly (the thing you put in service position) that controls the fans.

It is common for the rear mounted fan to jam due to a faulty vibration damper. When this happens, the control module will fail-safe and command the front fan on at full speed when the A/C is enabled. You would know by the sound if this has happened

bud4ya

I will listen this weekend and then post back up where the fan noise is coming from. The fan noise is only on and on all the time when AC is on. As soon as I shut AC off the fan noise goes away. I also noticed one time when I shut the car off the fan ran for like 10 mins after car was shut off but it may be made to do that not sure.

The noise does not sound like there is an issue I just noticed it constantly runs when Ac is on. I will do some listening this weekend and post back. Thanks everyone for the feedback