hello,
I have a Question.
Last night in Seattle, we had some snow and it was about 19F degree this morning.
GF's 2008 ML was parked out side all night, and this morning, ML was warming up for about 15mins before we hit the road...
as soon as we turned right ,, the foglight warning sign came up on the computer screen... (cuz..foglight turns on when we turn right, or left.)
we stop the car on the side of the road and checked.
The bulb and the whole covered glass was blown up..
is it something could happend? this cold weather?<!-- google_ad_section_end -->
I called dealership, it won't covered by warranty cuz they don't know it hitted by rock or any reason. it sucks......

 

take it to the dealership and talk to the service manager in person if the fog is the stock fog bulb. someone else posted an exploded foglight, but it was aftermarket bulb. stock bulb should not be exploding in your light housing, which is probably also damaged and needs replacement.

 

cold weather + hot lamp = explosion

 

its not even the bulb......
whole fog lamp and cover glass was blown...
I went to MB service today, they all said, never happen before.

 

Mercedes won't cover it,..........................ddddamn it.

 

Glass and plastics are extremely brittle when they have different temparatures on either sides. ie. Having A/C on high, on a really hot day.

 

You said it snowed... was the parking lot you were parked in plowed? Like snow piled on the side of the parking lot at the head of the spot? Maximas used to have a common problem with foglights cracking in similar fashion and the cause seemed not to be the difference in temp from the foglight to the ambient air temperature (like I had orignally thought too) because the temp swing is gradual. The cause was having the foglight on and hot and then parking and pulling the car in just a little too far and hitting the snow. *THAT* temperature difference is a lot and instant. That'll crack your foglights and I'd be willing to bet that's what happened. Since my wife stopped pulling INTO snow banks, she hasn't had a problem. The first set of foglights that we had to replace were under insurance because I got the adjuster to agree that the deer that my wife hit caused the foglights to crack