Center vent: Fresh air or hot?
 

On every Benz I have owned, the center vent has given me either fresh or cold air. On my '98 ML320, the center vent blows hot air like all the other vents and I HATE IT. Are the center vents on the w163 supposed to do this, or is it not operating correctly (I hope)?

Yes, that's how it is. You can just shut the center vent off.

Gilly

You can't shut it off completely. Hot air still escapes. While other occupants want hot air blasting through the cabin, I'd like some relief. Give me some cold air on my face. That's one of the best features of a Mercedes. I can drive in comfort while still accomodating the other passengers. I have this on my w123, w126, and w201.

If this is the new trend, I'll never buy new (or old new). I must speak to those engineers!

You should be able to shut off any of the dash vents completely. I believe there is a problem with your center vent assembly if you can't shut off the air flow, probably just the vent itself. I don't believe it can be repaired, needs a new vent assm..
I agree, it would be nice to be able to independently select a hot or cool flow from the vents. It seems like this is a possiblity only on the more upscale Mercedes, like the S, SL and CL models.
The redesign at least attends to a few of the complaints. It's cold enough here in Wisconsin now that hopefully I can get a feel for the climate control in real cold weather. The last time I had the service truck was around Christmas, and it wasn't all that cold around here.

Gilly

The vent does close when you turn the wheel, but you can still feel heat around the vent with just a little escaping. It's not airtight. It's definately not like the center vent on the other chassis. They close with an airtight seal that won't let anyting ascape.