E63 windows steaming up

[Hausi]

I have a 2014 E63 estate. The windows seem to randomly steam up or steam up during light rain/ drizzle. The only way to clear them is have the heater on max. The steaming up starts on the drivers side at the top corner of the window and quickly spreads through the car.

Checked all common causes; Windows are spotless inside. Cabin filter is new. Drains aren't blocked. AC works and is not on recirculate. MB can't find a fault with it but it's driving me crazy and at times is getting dangerous. Have I got a leak somewhere?

Anybody else have a similar problem or know a cure short of changing the car, which I am getting tempted to do?

Thanks.

 

[S2000Paul]

Auto and AC and no problems in my saloon, occasional puff onto drivers window if vent open and pointing there, in wet conditions, on start up but clears in 10 seconds..

 

[Deleted member 6183]

Do you sweat a lot?

 

[Dec]

I have a 2014 E63 estate. The windows seem to randomly steam up or steam up during light rain/ drizzle. The only way to clear them is have the heater on max. The steaming up starts on the drivers side at the top corner of the window and quickly spreads through the car.

Checked all common causes; Windows are spotless inside. Cabin filter is new. Drains aren't blocked. AC works and is not on recirculate. MB can't find a fault with it but it's driving me crazy and at times is getting dangerous. Have I got a leak somewhere?

Anybody else have a similar problem or know a cure short of changing the car, which I am getting tempted to do?

Thanks.

Perhaps you haven’t got your air con on and that’s why the are steaming up, do you have your air con on all the time?

Dec

 

[rOckyAMG]

I'd check your windscreen.

 

[ChrisCLS55]

Mine does that, I don't use air-con, every car I’ve had does that, quick press of the heater fan and it goes within seconds. I bet you wouldn’t get that in a country with a hotter climate...

 

[ChrisCLS55]

I just reread your post sorry. Mine only does that when I’ve parked it up and then go back to it after a short while.

 

[whitenemesis]

I have always used the a/c, it's on permanently, winter, summer, rain or shine. It dehumidifies the incoming air and helps dry damp mats.
I have never noticed any detrimental effect on mpg, I tried a few times over the work commute, nothing significant.

Switch the a/c on, set the control to desired temp and leave it on auto

 

[Hausi]

I have the air con on all the time and it works keeping the car at the desired temperature etc. I'm at a loss, MB seem to be at loss. Perhaps the windscreen is leaking. It's genuine MB but could be a replacement.

 

[clk320x]

I have always used the a/c, it's on permanently, winter, summer, rain or shine. It dehumidifies the incoming air and helps dry damp mats.
I have never noticed any detrimental effect on mpg, I tried a few times over the work commute, nothing significant.

Switch the a/c on, set the control to desired temp and leave it on auto

My car only has an ‘AC off’ button. So I assume even with the temp on 26c the AC still works?

 

[whitenemesis]

Have you lifted the foot well carpets to check the underlay is damp?

 

[whitenemesis]

My car only has an ‘AC off’ button. So I assume even with the temp on 26c the AC still works?

What year is the car? The meaning of the led on the button changed in May 2005. Prior to that date the led is on when the a/c is off. After that date the led is on when the a/c is on

 

[clk320x]

What year is the car? The meaning of the led on the button changed in May 2005. Prior to that date the led is on when the a/c is off. After that date the led is on when the a/c is on

It’s 2003

 

[Dec]

I have the air con on all the time and it works keeping the car at the desired temperature etc. I'm at a loss, MB seem to be at loss. Perhaps the windscreen is leaking. It's genuine MB but could be a replacement.

You have your climate control set to the desired temperature, hot warm or cold, in automatic mode, but, is the AC on or off?

Dec

 

[Hausi]

Temperature is set. Both automatic mode and AC on.

My old X5 used to have some form of fog sensor and knew when the windows were steaming up.

 

[grum71]

I remember reading (a long time ago now) that, if you use air con you need to shut this off about 1 minute before home (turning off the car) to allow the valves to close as the condensate enters the cabin. Bizarre but, I have tried this and it does make a difference.
Mine similar in cold weather and after washing the thing. Takes ages to demist. I plonked the de-humidifier in the boot for a couple of hours which did make a difference.

I always plonk one of these on the dash when I park up (moisture trap) - also good in the bathroom, conservatory etc:

Dehumidifier Interior Damp Trap Moisture Catch Mould Mildew Remover Home Caravan | eBay

Older BMW's (pre 2005) are renound for needing the air con on at all times. Normal fan mode always makes the car steam up. Bloody nightmare (and annoying)

 

[c_200k]

I have always used the a/c, it's on permanently, winter, summer, rain or shine. It dehumidifies the incoming air and helps dry damp mats.
I have never noticed any detrimental effect on mpg, I tried a few times over the work commute, nothing significant.

Switch the a/c on, set the control to desired temp and leave it on auto

Yup same here