Air recirc/fresh....

[Jake335i]

I was working on my car trying to clear a SES code with my scan tool and saw a fault:

Fresh Air/Air Recirculation flap motor - it was highlighted in yellow so I believe that means it is a "past" code and not presently found..??

Anyway, I leave the fresh/recirc air on "A" (auto) mode. However hitting the button does not create an increase in fan motor sounds, as it does with all of my past vehicles.

I have only had the car a few months, when I got it it really smelled, after deep cleaning, new cabin filter, removing the decayed bird from the intake, among some other tricks, the smell is completely gone. Anyway, how do I know if the system is currently working or not??

The plastic flaps in the front of the engine, always seem to be closed....not sure if that is the same system or not...?? Perhaps that is just a engine warm system to warm the engine faster in cold weather...??

Any way to test, or at a minimum, just get the system set to "fresh air." The fan has always seemed a little loud to me, if I had to guess I think the system is stuck in recirc mode...

Thanks in advance...

[David.X5]

The flaps in front of the engine are bypass for the radiator fan. unrelated to this question. The fresh air flaps are behind the cabin air filter which is in the engine bay at the firewall.

There is an F.Aux sensor next to the radiator fan that measures outdoor pollution and is one input in the auto mode for the recirculate function. They go bad after a decade or so, so perhaps yours is reading something that is forcing the system to stay in one mode or the other.

You should still be able to manually toggle between manual recirculate, manual fresh air, and auto.

[David.X5]

I can see the flap motor going bad or being bad. If you have a Bentley manual (if not, get one!), look in section 640, starting on page 640-11.

The fresh air /recirc motor is on the left side of the IHKA housing (center part of the dash that has the blower and all the ductwork), towards the front of the car. It can be accessed by removing 2-3 panels. You are lucky and don't have to pull the whole dash...

[Qsilver7]

Here's some info on how the AUC (auto recirculation) system works.

When NO LEDs on the AUC button is illuminated...the fresh air flaps are OPEN

Press the AUC button once (left LED illuminates)...you're in "A" (auto) mode...the flaps fresh air flaps and recirculation flaps close/open on a schedule based on data from the AUC sensor in the engine bay. So you won't necessarily "hear" anything like a change in the sound of the blower just because you pressed the button once.

If you want to specifically close the fresh air flaps (and probably hear a change in the blower)...you press the AUC button twice so that the LED on the RIGHT side of the re-circulation button is illuminated:

[Jake335i]

Originally Posted by Qsilver7

Here's some info on how the AUC (auto recirculation) system works.

When NO LEDs on the AUC button is illuminated...the fresh air flaps are OPEN

Press the AUC button once (left LED illuminates)...you're in "A" (auto) mode...the flaps fresh air flaps and recirculation flaps close/open on a schedule based on data from the AUC sensor in the engine bay. So you won't necessarily "hear" anything like a change in the sound of the blower just because you pressed the button once.

If you want to specifically close the fresh air flaps (and probably hear a change in the blower)...you press the AUC button twice so that the LED on the RIGHT side of the re-circulation button is illuminated:

Thanks after messing with it more I do detect a slight increase in sound when switching to recirc....looks like it is working after all.

Thanks to all who replied.