Center vents 1984 300SD - PeachParts Mercedes-Benz Forum

mrNewGuy · #1 06-09-2011, 04:21 PM

Hey all,
So...it turns out my A/C DOES work, which is awesome. However, I believe I need a new fan clutch (semi-expected) and the center vents do not seem to be blowing out any air. The defroster seems to be blowing out on any setting however.
I have tried looking through the posts but can't seem to find anything specific to this. Are there any quick troubleshooting I can do or any links someone can point me to? Is this going to require removing the dash also or just the center console? From what I've seen, the center vents are problematic.
As you can tell I'm a noobie, but I'm learning....I have a manual on CD but it's lacking in several areas and the best advice is usually been there done that kind.

thanks in advance.

tyl604 · #2 06-09-2011, 04:26 PM

On my 81 300SD the center pod is stuck open. So it blows defrost and heat toward the windshield just fine during the winter. However it also blows AC during the summer and fogs up the windshield. It is such a pain to get to the center pod that I just cut a couple of cardboard inserts for the defrost vents, painted them black, and stuck them in the holes near the bottom of the windshield. Now I get excellent AC blow through the console vents, and I just remove them during the winter.

big d · #3 06-09-2011, 10:49 PM

I have a same problem on my 1992 300 D.Just start today doing this.It hapened once before but after I restart car it was OK.

ROLLGUY · #4 06-09-2011, 11:22 PM

The solenoid that controls the center vents is behind the CCU. You can test the pod with your vacuum tester (every MB owner should have one). If it is bad, the only way to replace it is to remove the dash. If it holds vacuum in both directions, your problem is in the solenoid, or CCU. You can access the center pod by removing the glove box. Although I have not tried it, I have heard one can remove the pin from the actuator rod, and the flap will remain open and direct the air through the center vents.

dcotejr · #5 06-10-2011, 09:33 AM

I used the stick in the vent trick until I could get the vac pod replaced. (It tested bad)... Need that cold air here in Alabama!!

mrNewGuy · #6 06-14-2011, 10:18 AM

Thanks guys, appreciate it.

chrisbus · #7 06-14-2011, 11:03 AM

The vents are fairly easy to remove, and once removed, you can stick your hand in the vent opening and manually move the flap that directs the air between the center vents and the defroster. This flap is also controlled by the center slider underneath the vents (there are 3), however the rod that connects the slider to the flap can be easily removed.

To remove the vents, insert a small flat object (flat head screwdriver, for example) into the little tabs on the left and right center of the vent. Pry those tabs out and pull the vent out from each side as you do. I removed all of my vents and cleaned everything up...amazing how dirty they get!