Windscreen keeps fogging up

[muxmax]

Does anyone else have the problem that the windscreen keeps fogging up from the outside? I would like to find out if this is a general design fault or an individual problem with my vehicle: The AC outlet in the dashboard keeps blowing cold air which leads to the windscreen constantly fogging up from the outside in humid conditions; be it rain or just higher humidity outside. I have tried turning off the AC (btw: does anyone know whether the light means on or off?) and switching the fan setting to all possible other directions. That only led to the windscreen fogging up from the inside. The AC being set too low doesn't seem to be the problem either since today the problem occurred with the temperature set to 20 C at an outside temperature of 18°C. It would be helpful to get your responses.

 

[BobC]

I noticed that on auto setting, there is always some air blowing out of the windscreen vents. I just turn off "auto" and manually set the vents to front facing or feet or both, but still with AC on and temperature set. No more issue. As long as there is no air blowing on the windscreen directly you can still have the other vents blowing at whatever temperature you set with the centre knob. This solution also results in slightly higher air flow out of the front vents.

I came to the same solution as you. The only thing I have not sorted out is when manually controlling the flow/ temp vs auto I need to hand fly the cabin temp ( constant fiddling). The minute I click on auto some cold air gets directed to the windshield regardless of how the air flow selector knob is set. Any thoughts, tips or tricks would be most welcome.

 

[Bihner]

I too am having the same problem. I live in Houston with high humidity. There is always air coming from the windshield vents. I'm thinking of trying some Rainex on the windshield. Had anyone tried this?

 

[Shaky]

Try this it’s very good.

Glaco DX + Glaco Glass Compound Roll On

soft99store.co.uk

I’m not a fan of Rainex

 

[Phred]

I have found that if you keep the diverter selected to dashboard and feet, it does not fog up the window. If you select to just dashboard, you will get some leakage into the defroster and get fogging.

 

[RYAustralia]

I have found that if you keep the diverter selected to dashboard and feet, it does not fog up the window. If you select to just dashboard, you will get some leakage into the defroster and get fogging.

I tried that to no effect.

I tried putting on heat to full, manual full fan, then selecting each of the vent positions in turn for a couple of minutes each. That seemed to free up movement of the mechanism and the the diverts started working as they should .Someone on this forum had suggested it a while back, and yes that seems to work to free up presumable sticking vent flaps. Hopefully this fix will last a while.

 

[[ Adam ]]

Use the airconditioning, it dries the air.

AWo

Not outside the car

 

[AWo]

Not outside the car

Yes, but that is physics....and you can't come around physics....(except you're from the Newton family which was able to apply laws to physics).

AWo

 

[NotHerDecision]

I’ve been watching your thread as well. I’m in Houston and have the same issue. Seems like the dampener doors are leaking past where they should direct airflow. Has anyone taken this to the dealer to be addressed?

 

[bemax]

Yes, but that is physics....and you can't come around physics....(except you're from the Newton family which was able to apply laws to physics).

AWo

Do not forget Mr. Musk. For him physics are a thing to overcome as well (at least when it stays between him and his project/dreams like for example Hyperloop?

 

[Bihner]

I tried using the heater as recommended by other users and that did the trick. No more air coming from the windshield diffusers. Thanks to all of you for the helpful advice!

 

[Justaninternetdude]

OP I understand your problem completely, some others do not read correctly.
Using the wiper every 5 seconds is not a solution nor is "use the ac" or "just adjust your vents"
I have this problem in my GLS450 as well but only on the passenger side. Cold air from the AC blows on the windshield at the defrost vents. The condensation goes halfway up the windshield and comes right back after using wipers. Most likely we have a blend door malfunction either with the control mech or the motor/flap itself. My vehicle is getting looked at as we speak.

 

[Bluesurf]

We had the same issue with 5 BMW's over the years. This is crazy.