Rear window defog died in time for winter, anyone else?

[ezevphl]

Mine suddenly stopped working over the last few days. I tried a reboot and no apparent change.
Since its only evident during rain or snow I'm not completely sure if its working today or not.
The only evidence is that there is no distortion through the rear window, so I assume it doesn't work.

Has anyone had this issue? I'm hoping there is some sort of a quick fix and its not a total glass replacement.

 

[dendenyc]

Mine suddenly stopped working over the last few days. I tried a reboot and no apparent change.
Since its only evident during rain or snow I'm not completely sure if its working today or not.
The only evidence is that there is no distortion through the rear window, so I assume it doesn't work.

Has anyone had this issue? I'm hoping there is some sort of a quick fix and its not a total glass replacement.

I've experienced something similar, I was told that the M3 has sensors that prevent the defroster from turning on if the outside temp is more than X degrees. Basically it works when its cold and does not work if its too warm out. Freaked me out the first time too.

 

[ezevphl]

I've experienced something similar, I was told that the M3 has sensors that prevent the defroster from turning on if the outside temp is more than X degrees. Basically it works when its cold and does not work if its too warm out. Freaked me out the first time too.

Seriously? thats ridiculous.. Temperatures have been up for a few days, but how else am I supposed to defog the rear window in rain and foggy conditions?

 

[dendenyc]

Seriously? thats ridiculous.. Temperatures have been up for a few days, but how else am I supposed to defog the rear window in rain and foggy conditions?

I know, its annoying and I hope they address it soon with an update. I usually turn on the backup camera until the climate control inside hte car can do its thing.

 

[ezevphl]

I know, its annoying and I hope they address it soon with an update. I usually turn on the backup camera until the climate control inside hte car can do its thing.

Well I guess the upside is that mine may not be broken. I've been using the camera too, sigh.

 

[nvx1977]

Seriously? thats ridiculous.. Temperatures have been up for a few days, but how else am I supposed to defog the rear window in rain and foggy conditions?

are you against running the HVAC in auto? doing so automatically dehumidifies the cabin air so no fog can form on the glass.

 

[dendenyc]

are you against running the HVAC in auto? doing so automatically dehumidifies the cabin air so no fog can form on the glass.

TIL

 

[ezevphl]

are you against running the HVAC in auto? doing so automatically dehumidifies the cabin air so no fog can form on the glass.

I'm not. Honestly in temps above freezing I get in the car in my jacket and tend not to run hvac on shorter trips.
I've always used rear defog/defrost in to help clear the window when I don't have a rear wiper.
I'm assuming that the defrost can't be less efficient than heating the whole car.

 

[ItsNotAboutTheMoney]

I've experienced something similar, I was told that the M3 has sensors that prevent the defroster from turning on if the outside temp is more than X degrees. Basically it works when its cold and does not work if its too warm out. Freaked me out the first time too.

Another item for the list.

 

[ezevphl]

So I just spoke to the service folks and they said there is no temperature limitation above which it wouldn't come on.
I will try another reset and then will wait for the mobile service team if it doesn't work.

 

[nvx1977]

I'm not. Honestly in temps above freezing I get in the car in my jacket and tend not to run hvac on shorter trips.
I've always used rear defog/defrost in to help clear the window when I don't have a rear wiper.
I'm assuming that the defrost can't be less efficient than heating the whole car.

as far as I can tell, the dehumidifying is just the A/C compressor running at a lower power than regular A/C operation. It uses less energy than the resistance heater. I'm a bit stingy with HVAC use because I like gamifying efficiency in my car. I find that just running the HVAC on auto for a minute dehumidifies the cabin enough for a short trip so that it doesn't fog up. this is with ambient in the 30s. I'm sure fogging will get worse as temps continue to drop in the next few months.

 

[Vines]

So I just spoke to the service folks and they said there is no temperature limitation above which it wouldn't come on.
I will try another reset and then will wait for the mobile service team if it doesn't work.

You didn't happen to tint the rear window did you? I'd check the connection to the defroster, it might have some damage.

 

[ezevphl]

You didn't happen to tint the rear window did you? I'd check the connection to the defroster, it might have some damage.

Didn't tint, or otherwise modify the car. Front bumper was damaged recently, but thats about it.
Will see what happens after a total reboot.

 

[dendenyc]

So I just spoke to the service folks and they said there is no temperature limitation above which it wouldn't come on.
I will try another reset and then will wait for the mobile service team if it doesn't work.

hehe, I had this experience too...service told me no such thing, but when the rangers came out they tested continuity across the heater coils to see if they were broken. When everything came out clean they explained about the temp cut off sensor