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.

 

[Mkachilli]

I tried all of that but there is always air coming out of the windscreen vents irrespective of any settings that I change. So the outside lower windscreen always mists up outside whoever the A/c is on - which is 100% of the time when it’s 32 degrees outside with 90%+ humidity. Up here in the tropics that inability to switch off the windscreen vents is a real pain. Dealer said others have complained too but no fix from Ineos offered.

Hi RY Australia
Apologies if your thread has already been resolved, I am new to the forum and just picked up my Grenadier today. I live in Brisbane and you well know the humidity and high outside air temps we have right now, and I am having the same problems with constant cold air coming out of the windscreen vents regardless of what setting I have the HVAC controls set to. The windscreen is constantly fogging - have you found a solution ?

 

[travelguy2500]

Same issue for me in South Florida

 

[Skydance]

Read the section about HVAC. Have the system bleed. There is a Ineos procedure and then top up both coolant tanks, both high and low pressure. This will fix 90% of the HVAC issues and condensation.

 

[C-Mack]

With regard to window fogging a simple check is to make sure the recirculating button is “not” turned on. Otherwise you’ll be recirculating moist cabin air and it will constantly accumulate/condense on the colder window glass. Running defrost mode should also help dehumidify the air as it uses the A/C air drier to draw out moisture assuming your system is working correctly. Usually the biggest contributor to window fogging is keeping the recirculating button on by accident especially in lower humidity environments.

 

[RYAustralia]

With regard to window fogging a simple check is to make sure the recirculating button is “not” turned on. Otherwise you’ll be recirculating moist cabin air and it will constantly accumulate/condense on the colder window glass. Running defrost mode should also help dehumidify the air as it uses the A/C air drier to draw out moisture assuming your system is working correctly. Usually the biggest contributor to window fogging is keeping the recirculating button on by accident especially in lower humidity environments.

Definitely not the issue in my case. Recirculating definitely not active. I almost never use that.

 

[bigleonski]

Definitely not the issue in my case. Recirculating definitely not active. I almost never use that.

Bugger, I thought we had found a solution.

 

[DenisM]

My windscreen "fogs" on the outside on days of high relative humidity due to condensation caused by cold air from the windscreen vents even though the "mode" is set for cabin/face/footwell etc. An occasional swipe with the wipers clears it. My take is that the plenum flaps are not properly closing to redirect air away from the "demist" function....

 

[C-Mack]

Bugger, I thought we had found a solution.

If folks are having HVAC issues with vent doors/flaps on early production builds not working properly it’s entirely possible the recirculating door is stuck closed, and the button when selected on/off, isn’t actually doing anything. Other problems could be moisture getting into the cabin from leaking door seals, safari windows, as well as through the cowling as I believe there was a potential leak source from a water drain?

I guess it could be possible the HVAC system in general isn’t capable of removing enough moisture from the inside of the vehicle in high humidity regions to keep it from condensing on the glass but I doubt that is the case.

For fogging on the outside of the glass I wouldn’t begin to speculate what the cause of that would be unless the A/C is constantly stuck on and aimed at the windshield and warm outside moist air is condensing on the glass is supercooled from the inside.