bzliteyear

hi guys,

not sure why but my two center vents have no air flow, but the two side vents are fine. this is both for AC as well as just econ air. i thot perhaps it was just some simple connection, but a friend at a body shop said it was electronics related and needs to go to dealer. anybody w/ idea on the problem and also the fix, cost, etc... thx.

michakaveli

It depends on the blower setting on the climate control. On mine sometimes it works and sometimes it doesn't. Usually does blow air but very very light. Then other times it blows strong... I assume it's climate electronics related.

aglasgow

The vent flaps are controlled electronically by the climate control module so it's not unlikely that there may be something wrong there. Your dealer/tech should be able to perform a flap test right from the climate control panel in diagnostic mode to determine this.

6.3

What temperature does it happen in. When you set the temp high for heating the middle vents do not work. I think it's explained somewhere in the manual. I will need to recheck the manual but I think it is designed that way. If you set it for cool temps the middle vents should work, given that they are open.

bzliteyear

thx for reponses.
the two center vents are both VERY light, barely there...regardless of whether HOT or COLD. sounds like i need to take to dealer where they immediately chg me $100 before telling me anything

michakaveli

Peep this guys ... it fully explains this phenomenon. This photo is off the w210 tech cd.... Enjoy

6.3

THis confirms that no hot air should be going out from the cnter vents and it sort of makes sense for the hot air to go from the bottom up. However if you have the AC on cold and the center vents are open on AUTO ou should have cold air coming out of the center.

MKW

Do the " flap test " under CHART 2 Climate Control self diagnostics from dash panel

Tim-BlackE320

thanks for the graphic, michakaveli. I was wondering the same thing. Good to know that I d/n have to have this checked out.

michakaveli

It's nice to share tangible information.

Cary Collier

I wish I could see the image?? I have the same issue.

Plutoe

Not applicable here, but a great FUYAA------see post 8 for the correct direction

khorrassany

Hi I have the same issue so was going thru the threads and the link posted is not working. Can you please repost a working link, thank you

Plutoe

Do a google search as the flap test is all over the internet

raymond g-

scroll down to AIR CONDITIONING, FLAP TEST.....

MATTDOJERMAN

I had the same issue in my car and it took me forever to figure it out and not having the center vents blowing in the summertime especially in Arizona when it gets up to 115°, is not the way to go. So on the top back side of the intake manifold under the hood is a small vacuum line that runs behind the firewall there's a gray vacuum hose coming from the passenger side of the vehicle where the ECU and everything is the hose from the intake manifold connects to the vacuum line if it disconnects for brakes your center vents won't work mine came on hooked and the moment I hooked it back up the center vents were back to working

bbirdwell

And the hard line usually breaks at the snap connector adjacent to the Duo-valve on the passenger side rear engine compartment (left-hand drive).

AndyFC

Is there anyway you can post pics of this??? I think I’m having the same issue. I’m getting very little airflow to the middle rear vents and to the middle passenger vent and the driver side foot vent is always open regardless of setting. I have a 2001 c320

MATTDOJERMAN

So if you're driving a Mercedes like mine the 2001 e320w210 you have a central vacuum pump under the back seat that controls your air vents your door locks your trunk pop and a few other things that would cause your center vents not to blow another cause would be you have a vacuum line under the hood that connects to the back of the motor if that line breaks or comes becomes disconnected that would also cause the same issue center vents front of the car not working