W212 Air Condition Malfunction
 

I have a 2010 Mercedes E350 4 matic. It just started to get warm here in Virginia and I now have to use the AC. So here's the situation that I'm having.

In the morning right after I just started the car, I will turn the AC on. There's air blowing but no cold/cool air coming out. Even when I wait for a few minutes or even if I turn the AC off and On. Nothing.

Now I would turn the engine off and restart it. I turn the AC power on and the AC works perfectly fine.

Freon is perfectly fine. No leaks.

There's also time when I use the heater that on the left side is cool and the passenger side is hot even though the control panel is set to the same temperature.

Anyone else had or have this same problem? Anyone know what needs to be replaced? Thanks in advanced.
https://cimg0.ibsrv.net/gimg/www.mbw...0f5de5f902.jpg

There have been some other threads with similar issues. No solutions though as the problem appears intermittently (and folks don't always post resolutions). Check out the other threads and maybe one of these sounds like your issue.

https://mbworld.org/forums/e-class-w...t-cooling.html
https://mbworld.org/forums/e-class-w...mittent-c.html
https://mbworld.org/forums/e-class-w...-problems.html

Nice pic btw

I would get the car scanned. There's a bunch of temperature sensors that could be bad or it could be something else. At least with a scan you'll have a place to start. There's lots of scanners out there now that will scan MB specific codes, Autel Diaglink, icarsoft, icarscan, carly, etc.

Thank you for this update thefisch. I will look through them. Appreciate the like on the pic. I really love the car and don't want to let it go because of this. Hope I can get a solution for it.

cetialpha5 I will get it scanned next week. I will see if there's any code at all. It's just frustrating having some problem and not knowing what needs to be replaced.

I believe that's a variable displacement compressor, if you have the modules scanned ( not just generic obd2) it should show sensor inputs and what the control module is commanding. I had a similar intermittent issue but the compressor was replaced under warranty. My guess from the info I got was that there may have been a defective control solenoid at the compressor.
I hope you post any final info or fix, helps us all.

For last 20+ years MB makes digital controls on HVAC system, with minimum of 7 sensors, so you won't go far in troubleshooting without reading the sensors.
From several sites giving advice, I found this one giving the most straight advise http://www.mercedesmedic.com/ac-air-...le-codes-list/
It shows climatronic from W210, where you could read the sensors without scanner, but with newer models you need a scanner.
Follow the sensors reading procedure in notes, check for codes and clear them. If you can't interpret the data, post it here and I will try to help.

So when your compressor was replaced, the problem was solved?

I just got back inside the house after trying the steps on that link. Only problem is, I don't have the REST button. I'm guessing the US versions don't have this?

Yes.
But bear in mind in many cases the dealer will replace an entire component under warranty as its more cost-effective for them rather than repair a smaller part within that component. Again, verification of sensor data is key to identifying the problem.

You did not say what car you are talking about, but from my observation no W212 comes with REST button, so you have to use scanner.
My 2008 W211 come originally with no REST button, but I liked the in car troubleshooting so much on my W210, that I replaced climatronic with one that has REST button and allows me check AC while driving.
That is an option in W211 and would I found it for W212 I would jump on it as well.
Living in 120F weather you want to catch beginning of the problem, not be surprised with final failure far away from home.

All I can say is my AC is flakey as well. On some hot days there is nothing I can do to get it to work and then the next time I start it it works. Since it seems like it works fine when it works I am assuming nothing major is wrong with the system. One of the posts on the subject suggested that if it was marginal on refrigerant it could act like that. Had something to do with a sensed pressure and the system was trying to protect itself from running dry.

I had it checked for freon and its full. I will be getting it scanned on Wednesday, will keep you guys updated. Thank you all for the input. Hope we can get this resolved so everyone else that will have this problem in the future will know what needs to be addressed.

Alright everyone, I had the car scanned and the code was "Climate Control" the scanner that he used is not the same as the dealership uses but smaller one. It didn't give a number code, only "Climate Control" fault code. I tried researching it online but I'm not coming up with anything. Any suggestion?

Get a better scanner. When I had a problem with mine, it told me the sensor was in the passenger footwell and the indy was able to repair it, the wiring was bad.

I also went to a mercedes tech and he scanned it with the right scanner. No more code coz the other guy cleared it... geeeeez.. he did it so quickly and didn't even ask me if I wanted it cleared.

Well if you're still having the problem then I'm sure it'll come back eventually when you use it.

Good.
With no error codes you can go back to procedure listed in reply #7

Yes, we'll see.

Will do. Thanks

UPDATE:

The first guy who cleared the code earlier just informed me that the code was actually "CLIMATE CONTROL SOFTWARE"

Does this mean it needs to be updated??

Never have heard such description, but code number should explain it more?
MB keeps adding new programs to their cars, so maybe you are the first one who has to deal with new animal, but we are still walking blindfolded.
At this point, since 21 replies are not leading us anywhere, I would advise to take it to a dealer.

UPDATE:

So this happened again yesterday morning. Started the car and turned the AC on. Air blows but no cold air. I drove straight to my mercedes tech as he told me to come straight back to him when it happens again.

When I got there, I didn't turn the engine OFF

He hooked it up on the benz scanner and checked for codes

No codes were found at all

All clear!

He then checked the AC pressure

Found that the there's no pressure at all

Meaning the compressor is not running

So we turned the engine OFF and turned it back ON

We turned the AC ON again and the AC works like a champ!

His conclusion:
The AC system works fine. The Compressor is fine. Freon is at full. The Climate Control Unit is the culprit because when it's malfunctioning were there's no cold air is blowing even when the AC button is ON. The control unit is not sending a signal to the compressor to come on even when the AC button is ON. He is recommending to replace the Climate Control Unit itself. I've looked around and found some on Ebay for $99. Will probably have it done soon.

MB stop using freons about 25 years ago.
Your description makes no sense.
Once you saying the system is empty, other time it works just fine with good pressure.
You need to get the car to somebody who knows how to read the scanner.

I don't know where you got me saying that the system is empty. That might be why you're confused. I'm not the Tech, the Tech is the one that is saying this. Your saying Benz stopped using FREON?? OK......

Thanks for your input..