KHARBAT1

How do you switch between cold and heat on C320 Auto Climate control ? or is it auto based on the temp selection ?
I have not seen any buttons to show heat . the only button there is , AC off / reset ( the manual call it EC ) . When the AC light is on , the AC is not working , sounds backward ? Thanks for any input .

Glyn M Ruck

Older cars had the unintuitive light on = HVAC off. Temperature controls do the rest.

KHARBAT1

Thank you Glyn .

damian in nj

We're facing this now in the g/f's 05 C230K sedan. Is the evaporator the ultimate culprit? What do those run for a factory replacement?

PelicanParts.com

You might be able to find some help in our tech articles here. Otherwise, you can check part pricing in our parts catalog here. Good luck!

-Luccia

jvakos

I had this exact same issue my air conditioning would blow cold from passenger front side cents but was mostly warm from driver side vents.

Thanks to mbworld and these posts I figured out that this symptom (a/c only working from passenger side vents) is due to low refrigerant and very easily fixed with a cheap 45 dollar refrigerant tester and refill kit you can buy at pep boys. I have a 2003 c32 amg and didn't realize that after 8-10 years the refrigerant slowly starts to evaporate which is how my level was low but still providing some cooling (that's how I knew it wasn't a leak in the a/c system)

I will post pics of the refrigerant kit I bought and how you connect it, but it was super easy you find the LOW side a/c port which is on right side of engine bay next to air filter boxes and connect that to the refrigerant kit hose and gauge which tells you what the level of refrigerant is. If it is low you just press the trigger on the refrigerant can to release more refrigerant and watch the gauge slowly fill up to the correct level.

Cheapest fix I've done and my a/c now blows super cold from both passenger and driver side vents no matter if I put it on recirculate or exterior or if I use the filter options. Also that hissing noise I used to hear is about 95% gone and the a/c is super quiet. Also If on recirculate it gets extemely cold. It's like having a new car again!!!
Just in the nick of time too because Chicago Summer is here and it got up to 84 today and really hot but after this fix I could run my a/c and full max and it would get super cold even when I was running the a/c while parked in a lot testing the pressure.

Boom vang

I had the same issue 2 years ago, warm on driver's side and cold on passenger. the fix was a new receiver drier and expansion valve. The system was evacuated and then filled after the 2 parts were added.

I got this done by a moonlighting MB mechanic who said that it is usually one or the other. The pressure initially was fine but over time you need to replace the receiver drier and since it made sense to replace the expansion valve for $24 then charge the system only to find that that was the issue.

Bought both parts at RM Euro which sells the OE part for $24 and $36 [Engelhof and Behr Hella]

edstein

I have the same problem with my 2012 W212 E350. Warm air on drivers side and cold air on passenger side. What I need is to know if this is a DIY or do I need to take it to the dealer?
I have already been ripped off once and really don't want to go back to that dealer.

MrVu

Kind of an old post but anyways... Funny, I just had this issue recently too.


Our cars have 2 blend doors per side that control heat/cold. Your driver's side blend door could be stuck open in the hot side. If you are somewhat mechanically inclined, you can remove the lining under the steering column. Just a few bolts here and there.

It will expose the blend door. You need to run the ac at max settings, while you're looking at the blend door, rotate the temperature knob cold-hot and back and forth. You should see if the blend door flap opens or closes.

If it does work, then that is not the issue and you're probably just low on refrigerant.

Have a professional shop do this for you. They will recover and vacuum your system and see how much was in the car. For instance, they only recovered .0023 oz of freon in my car, the right amount would of been .87 - .90oz . After the covering of the existing refrigerant, they will recharge it from an empty system to calculate the exact needed amount for the vehicle.

So, most likely you are just super low on refrigerant and there may possibly be a leak somewhere in the system.

Good luck!

Edmu

How do you reset a manual climate control? (2004 C Class)