HELP! windscreen demister

Ive also just had the same problem, thatnks to all of the above for descritions and photo's, just re-installed my glove box and its working fine at the moment !

If you have a CD Autochanger located in the glove box you will also have to remove that before you are able to remove the glovebox as there is another bolt scerew that sits abouve the changer on the top row so there is infacet 6 bolt screws (4 along the top and two at the bottom of the glovebox
 
I've just joined this forum but looked at it yesterday as demister stopped working, following all the advise, I took the glove box out today and appears that the servo has crashed. I'll get one ordered and put back, hopefully this will do it. Great stuff, thanks for the advise. My 52 plate A4 1.9 has now clocked up 211,000 so feel I owe it a bit of TLC! Am going to put some of the broken bits back together, first off, the ash tray lid won't stay closed? Any ideas?
Thanks again for the servo advise.
 
Would this be the same for the heating as when my passenger side is set on cold it just comes out hot. Anyone have any idea what this could be?
 
Would this be the same for the heating as when my passenger side is set on cold it just comes out hot. Anyone have any idea what this could be?

did you get this sorted mate? i wouldn't imagine this would affect hot/cold as it's just the direction of air. But possibly one of the other servos and linkages is responsible for closing/opening the flow of hot air from the heater matrix.

Quick Question to the people who have done this - Is there a servo each side that controls the left and right side of the screen?
 
My screen demist (Centre Vent) and both dashtop side vents are today feeling breathless.
Does the green armateur servo drive the flap for all 3 vents dashtop/screen vents or is there another/sperate servos for centre and side demist.

What servo's are one the pedal side ?? for what vents ?

Face vent works fine as does the floor vent, but when I switch to top/screen vent no air comes out but you do get some floor heating.

When on the centre vent setting the floor heating closes off as expected. Revert back to screen and face vent goes off as expected, but floor opens again ?
 
the one with the green arms is for the centre vent only I'm not sure what the others are

When my centre vent went I just unscrewed the servo and pulled it down so it was open all the time! and from the advice of another member I opened the servo and cleaned it up and greased it put it back on then reset all the flaps with VCDS and all has been well since

I also had a potentiometer fault flag up on VCDS on one of them so I opened it up sprayed it with wd40 greased it all and its been fine since!
 
As stu-m says, it is possible to open up the little servo gearbox. There was a photo sequence of this on this forum last year, which I can't now find, which is very irritating as mine's just started doing it again occassionally. It seems as if the 2003 grease is starting to dry out now and everyone is getting this problem at about the same age - particularly in cold weather, tighter plastic and lower battery volts.
 
you dont need the pics to open them they are so easy

I did mine in about 5 mins there is little clips on the side use a small flat blade screw driver and work your way round carefully
 
What do you do once you have it open? Removed mine a few weeks ago but never got round to opening the thing up! Any how-to guides anywhere?
 
there is a how too guide somewhere

open it up remove all the parts clean then grease them and re assemble simple
 
As one member said, drop glove box and open stuck vent until you replace motor. Did it on my last B7 and it was fineto leave open as my main concern was to desist the print Windows
 
Is the glovebox removal any different for a glovebox with cool box? I'm guessing I'll have to disconnect the aircon hoses but any hiden screws behind the cool box?
 
Sorry cant help you there Paul.

Thanks to others as this helped me fix mine on my 2003 S4. Once i got the motor off and manualy moved it it started to work again, the glove box will stay on the floor till im satisfied its fully functional after reading that a few of you had to remove it several times lol
 
Well, I had the glove box out to fix the hinge and for future reference for anyone it's best you unscrew the fitting from the inside of the cool box first, when I removed my glovebox the pipe pulled out of the aircon unit, but it just twists back in there.

I took my actuator apart, removed the motor span the gears, lubed it a bit more, then plugged it back in and seemed to working fine. So time will tell but glove box is back in!
 
Hi, I bought my car on Saturday and this morning, which was a cold one, I had difficulty clearing the front screen. It seemed ok if I ran the blowers using only the arrow up button on the climate unit, however when I pressed the clear windscreen button, the fans seemed to engage into a different setting judging by the sound that was made, but the screen seemed to steam up really badly.
I reactivated the arrow up button which should also direct air to the window and it seemed to take an age to clear, which it did eventually. It also struggled if I had the cabin vents activated. I resorted to also opening the windows slightly as the whole car steamed up.
Does this sound like a similar problem, or possibly pollen filter?
Thanks
Chris
 
If you put the screen only on you should be able to feel air coming from the dash bent, if not then the motor might not be working correctly.
As you say the pollen filter could need changing, and also the inside of the windows might need cleaning, you will be surprised how much more they steam up when they're dirty.
 
Hi, yeah good point, the screen probably does need a clean as the areas where the stickers were when it was on the forecourt are the only places that stay clean. I'll check the pollen filter too.
 
Does your AC work properly? Sometimes they steam up badly without it.
 
Long time reader - first time poster. Great forum!

I've had an intermittent issue with the screen demister on my A4 so followed your advice here, took out the glove box, unscrewed the servomotor connected to the green arm, jigged it around a bit and it worked for two weeks. Happy days!

Anyhow, this morning , it's causing me grief and after loosening it again, it looks like it isn't really moving at all. (I think!)

What's the behaviour of these things when they are on the way out? Might it work for a week and give up totally? Is the servomotor attached to the green arm dependent on the others in some way?

The bit I really am scratching my head about!!! ..... How do I get the one attached to the green arm out? How do I disconnect the servomotor from the green arm?
 
I've just had my motor out and apart this evening! It only played up once but I wanted to save it from dying permanently. I greased the cogs with thick motor grease and then used silicone spray on all of the coloured moving arms. Hopefully this will extend the life of these bits.

To get the motor off of the green arm you need to remove the two small screws and then rotate the motor until the green bits slide apart.
 
To get the motor off of the green arm you need to remove the two small screws and then rotate the motor until the green bits slide apart.

Thanks for that MooLard.

So, the green arms will stay attached and I'll just have the motor. It's the two small screws keeping the motor in place?

Not even sure if the motor is still moving. It was a couple of weeks ago. It seems to be in a middle position at the moment meaning a clear windscreen but colder feet than normal! Cheers.
 
It's this time of the year when lots of posts about this problem seem to appear, just after Christmas spending, and at the colder end of the year!
Yes one small piece of green plastic remains attached to the black motor box but the rest of the green linkage stays there.
Once it's off move the linkage with your hand to see if it moves freely. You could potentially put voltage on the motor to test but I don't know what voltage is safe, so it's probably better to refurb and connect back up and try it with the glovebox still off and out of the way.
 
Where is this motor exactly- could someone circle it on the page 1 pic? Is the glovebox easy to get off? I might try it....
 
I cleaned and re greased ours and lasted for about 6 months but has packed up again.

Does anyone know if the motor inside is the same as any of the other motors as they are easier to get hold of.

Also ringed the motor for the demist flap that we are all talking about.
 

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What grease did you use?I used silicone which wont harden.Seems to me that it doesn't need much to stop it
 
I just used white grease as that doesnt harden.

I think the motors just get weak.
 
10 years+ later and this thread helped me too! Photos great, thanks Markyzs180 and co. Just moved the green linkage manually to allow windscreen demisting all winter - not up for spending any more on 250,000 mile the old beast now, unless strictly necessary!
 
Mine still isnt to be trusted .Moves nicely all summer then suddenly sticks and later frees itself randomly.I now leave the screen button on so that I have got demisting when needed and avoid going auto .Although its just passed another mot and drives well its not worth throwing time and money at whilst waiting to see how long its going to last or they offer a good scrappage deal