[pedrobmw]

OK so here was my issue,
No air flow to the windscreen!
I had been using my car all year with the three 'green' lights lit up,ie not using the climate control. Now the cooler weather is here I needed to demist the screen. I pressed the rapid demist button and the fan sped up the flaps closed but NO air to the windscreen!!!!!!
I read through hundreds (and hundreds) of forums about this and they all said the same thing! Stepper motor failure, dashboard out, major expense !!!!
I could have cried, the car was only just out of warranty. Talked to my mechanic ( also a very close friend luckily) and he came up with this, as the climate control had not been used the flap/stepper motor had got stuck!!!
Now this is how he fixed mine.
Switch off climate control.
Remove steering column shroud and all lower panels.
Lie on your back looking up,top of head next to transmission tunnel,look on the left side of the steering column and you will see 2 little black boxes with little red arms on them.
Switch on climate control, now alternate between screen and face mode with the green buttons.get a friend to do this!!
With a long thin screwdriver or other tool gently press the stuck red arm. It should start to operate, do this a few times and spray in some silicone spray and all will be well.
Mine is now working perfectly. I should just mention that if you need to renew the motor you can get at it by dropping the steering column. This job took less than an hour from start to finish!!!!!!!
I should just mention my car is a 2006 e46 325ci convertible rhd, I think if you had a LHD this job would be a lot easier as the steering column wouldn't be in the way.Its a relatively easy but very very fiddly job.
I hope this helps, feel free to ask any questions.
Moral of the story, use your climate control or screen demist regularly!! Pedro

 

[Bali]

Your first post and you are already passing good info to others. Thanks and welcome to the land of fanatics.

 

[jdstrickland]

I would suggest that you should wipe the stuck mechanism after you get it freed, or dilute the spray lubricant and leave the parts dry.

The trouble I see is down the line when the lubricant dries after collecting dust and dirt for several months. The goo created will have you back under the dashboard curing the same problem all over again. WD40 is a horrible product precisely because of this issue. It cleans sticky mechanisms, but when the carrier evaporates, the goo left behind locks up tight and the same problem comes back all over again.

I think that the mechanism gets sticky for whatever reason and needs to be cleaned, but if the mechanism is left dry then it will not attract the very dirt and dust that made it stick the first time.

Having said all of that, your diagnosis is spot on, the stepper motor is not very strong and while it tries to push and pull things around, the dirt and grime in the linkage prevents it from doing so.

 

[pedrobmw]

Thanks for the reply, yes I can see where you are coming from with the spray. However as my car is a RHD it was impossible to get into the flaps or motors without a major strip down.It was all we could do just to get the screwdriver in to tap the motors !! I guess if you were going to completely strip everything out then wiping all the components dry would be a good idea, but as I was restricted by time etc my quick fix was all we could manage and it all seems to be working perfectly. Fingers crossed. Time will tell I guess.

 

[pedrobmw]

Thanks for the reply, yes I can see where you are coming from with the spray. However as my car is a RHD it was impossible to get into the flaps or motors without a major strip down.It was all we could do just to get the screwdriver in to tap the motors !! I guess if you were going to completely strip everything out then wiping all the components dry would be a good idea, but as I was restricted by time etc my quick fix was all we could manage and it all seems to be working perfectly. Fingers crossed. Time will tell I guess.

 

[cfurfey]

Hi. I am having the same issue and could do with some help. When I press the button for windscreen demister the power ramps up but very little goes to the windscreen . . . Even when I close all the dash vents.

I have just removed all the trim under the steering column and can see the arm moving to open and close the vents.

I have also removed the filter but still no change.
After all this it seems the motor is ok . . . The actuator is ok . . . And the filter is ok . . . . . But I still have the problem.


Any help appreciated.

 

[invisible man]

Where is this on a LHD car? Mine is definitely sticky when it's cold.

 

[pedrobmw]

My car is a Rhd and once you have stripped away the trim you should be able to lie on your back and with a torch look up behind the dash and see the little actuators and their respective arms. There are 3 of them up there and one controls the demist vent. The easiest way to get at them is to dfop the steering column. I fixed mine however by getting a friend to push the 3 vent switches in turn and gently move the arms to get them going. Its a very very very fiddly job but it can be done. This is a common problem because the climate control is not used properly and they sieze. Once you get them moving set the climate control to your desired temperature press auto and just leave it to do its thing. It works very well.
I hope this helps you.
If you have any questions please feel free to ask me.
Pedro

 

[pedrobmw]

Oh sometimes the little actuator arm can spring away from the flap securing clip. It just needs clipping back on. This is a major strio down job. Dash out steering column down but can be done at home. If you can see your actuator arm move but not move the flap then I would guess this is what has happened. The flaps stick due to lack of movement and as the arm tries to push/pull it the clip just pings off.

 

[jdstrickland]

The linkage being discussed is at the top of the transmission hump, near the firewall, on the right hand side of the console stack. On a LHD car, this position is above the passenger side footwell, near the duct that puts warm air on your passenger's feet.

 

[cfurfey]

Thanks for the post . . Didn't think about the flaps coming loose. Something to try at the weekend

 

[robotsan]

I know I'm resurrecting an ancient thread, but just hoping someone else can help.

I think I've got the same issue as Pedro did 8 years ago - I press the windscreen button and nothing changes - air still comes from the same dash vents as before. However I'm also finding nothing is changing when I hit the 3 area buttons (face, middle, feet).. and I don't even hear any kind of movement or whirring.. so does this mean the motor to move the flaps is dead?

I've taken the lower steering wheel trim and the trim under that, but I can't see any red actuator arms at all. Just a green cable coming from the middle of the dash, connected to a yellow part which pivots with a black part (circled in red in the photo below), which I presumed opens the flaps to move the air to a different part. Now I'm writing this though I wonder if that is actually connected to the wheels on the upper dash / face vents.

I can see a part of something dark red, but it doesn't look like an arm at all (circled in blue below). But I don't know if that's the right thing and I don't want to go spraying stuff up there until I know. Can anyone shed any light on this for me?

Btw it's a 2005 RHD manual M3 coupe. I wonder if that makes a difference?

This is taken from my point of view when on my back looking up, with the pedals behind my head.