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Full AC is cold on Driver side but blows warm air on Passenger side
hi all,
I recently had my battery died and replaced it with a new one.
For the past couple days, I notice that only driver's side has cold air but passenger's side has warm air when AC is on full.
Could it be the battery that reset climate control unit?
Has anyone have the similar problem when changing their battery?
Thanks.
I got you.
I'll check it tomorrow and see if the connector is plugged in..
Thanks.
I popped that footwell cover when I was chasing the whistling from my Bosch OEM fan - Tiny temp sensor is toward the center. It looks like a 5¢ piece of plastic troubles.
Last edited by CaliBenzDriver; 06-15-2021 at 12:08 AM.
Once again, last season I say this. The flap that direct hot/cold air on that side is stuck on the hot side. Put your A/C to cold max then hot max the back to cold at least 6 seven times on the passenger side. That should lubricate the flap.
Once again, last season I say this. The flap that direct hot/cold air on that side is stuck on the hot side. Put your A/C to cold max then hot max the back to cold at least 6 seven times on the passenger side. That should lubricate the flap.
thanks for the mad tip.
You're saying exercice the HVAC temp actuators, that will help clean the internal contacts that were busy oxidizing 😃
Last edited by CaliBenzDriver; 06-15-2021 at 03:17 AM.
There's actually multiple temperature sensors. The one by the footwell going bad is pretty common due to the cabin filter. You need a scanner that can read MB specific codes to see if there are any other temperature sensors which might be bad.
check your freon level. Low freon will cause this to happen. My truck just did the same thing. I was a pound low on freon. Filled it up and I'm back to blowing cold on both sides.
Good idea to check the operation of the dampers for the heat. How cool does the air feel on the passenger side when the engine is cold? The coolant won't be warm yet so the heater core would not warm up the cooled air.
Another possibility is issues with your evap coil or TXV. If the evap coil is freezing over that usually affects one side first. Easy way to tell is first start in the morning when there would presumably be no ice left. If it blows cold on both sides then but starts blowing warmer later on, then icing over might be your issue. It's also easy to check the evap coil for ice - just pop out the cabin filter and stick a smartphone taking video up in the opening towards the center console. Inspect the cabin filter while you're at it.
The way you do it's non stop. Don't wait 2 minutes go all the way down then back all the way up.
I was skeptical at first but decided to give it a try..
I started at low then go to high back down low and go to high again.
That is when I hear a clicking noise, sound like something moving then holy@$&$&& cold air does come out from the passenger side.
The only thing left is center console on passenger side has weak air coming out but it’s still cold.
I think I still buy the scanner because my rear passenger side door won’t open. I hope scanning will at least give me some idea.
Anyway, thanks man.
Last edited by 2011WhiteE350; 06-16-2021 at 10:23 PM.
I was skeptical at first but decided to give it a try..
I started at low then go to high back down low and go to high again.
That is when I hear a clicking noise, sound like something moving then holy@$&$&& cold air does come out from the passenger side.
The only thing left is center console on passenger side has weak air coming out but it’s still cold.
I think I still buy the scanner because my rear passenger side door won’t open. I hope scanning will at least give me some idea.
Anyway, thanks man.
That flap is the bane of all W212's. I recommend to all of owners to do the cold to hot trick at least once a season, to keep the flaps lubed.
Once again, last season I say this. The flap that direct hot/cold air on that side is stuck on the hot side. Put your A/C to cold max then hot max the back to cold at least 6 seven times on the passenger side. That should lubricate the flap.
Thank you! I was having this same issue as OP, and after three up-and-downs, cold air started blowing out the passenger vents. I did a few more for good measure.
Thank you! I was having this same issue as OP, and after three up-and-downs, cold air started blowing out the passenger vents. I did a few more for good measure.
Some of my fixes sound a bit far fetch, and a bit easy, but they work. I like pressing life's easy button from time to time.
My 2010 E350 is doing the same thing. Cold on driver, hot on passenger. Just bought it 6 weeks ago (in January). AC seemed to function then. Now, on a 78 degree day, I'm having the issue. What did you ultimately do to fix yours. I scrolled through the thread and found a bunch of different suggestions but it is easier to ask the initial poster! Thanks a bunch!
Originally Posted by 2011WhiteE350
hi all,
I recently had my battery died and replaced it with a new one.
For the past couple days, I notice that only driver's side has cold air but passenger's side has warm air when AC is on full.
Could it be the battery that reset climate control unit?
Has anyone have the similar problem when changing their battery?
Thanks.
My 2010 E350 is doing the same thing. Cold on driver, hot on passenger. Just bought it 6 weeks ago (in January). AC seemed to function then. Now, on a 78 degree day, I'm having the issue. What did you ultimately do to fix yours. I scrolled through the thread and found a bunch of different suggestions but it is easier to ask the initial poster! Thanks a bunch!
Move the temp setting from highest to lowest repeatedly. That worked for me.
06-14-2021, 10:51 PM
Full AC is cold on Driver side but blows warm air on Passenger side
