austin94

Just curious, has anybody had any issues with their HVAC system in their W212?

I think My compressor many need replacing, and I just cannot fathom that my W210 still has the original compressor, along with my 2000 Ford F250 and 2007 GMC Yukon, yet my "trusty" W212 may need replacing....

thefisch

No issues here. What's happening with yours?

austin94

Sometimes my AC just will not get cold! Other times it runs fine. I had the refrigerant checked and it was within the norm so my guess is the compressor is failing? I find that hard to believe since my 01 W210, 08 W211 07 GMC Yukon, 2000 Ford F-250 all have original compressors! But I'm not sure what else could be happening.

Arrie

Could be the gates that mix air for the set temperature...most likely reason for the trouble after refrigerant checked out fine.

aquinob

That's a bit of a jump to call it the compressor when it may be something as simple as a sensor. Is that what the guy who checked the refrigerant said? If it gets cold at times, I would not fault the compressor, either it works or it doesn't, its just a pump.

thefisch

+1. If you set the car to max cool and it blows cold for several minutes your compressor is likely fine.

If you are running the climate system in auto, the problem is you can't always tell what is going on. If max cool works, I would run it manual for a while to be sure it can get hotter and colder when you want, blow out the vents you want, etc.

jonUF02

Mine is cold as He!! - 2012 E550 in FL.

nhoj_yelbom

its the switch on the compressor, mb replaces compressor to fix. i have not checked for a replacement for it. good luck

thefisch

any update on this?

austin94

Still having trouble months later.... the problem is just so intermittent it's hard to pinpoint.

Any idea how exactly to test the switch in the compressor?
I don't want to spend $150 diagnosing it at the dealership to have them tell me something I can figure out myself...I know I'm cheap.

Thanks in advance!!

Chris_tA_4

I have the same problem. My a/c is intermittent. I've just been dealing with it

cetialpha5

Could be lots of things. I think in the W211, there was a valve that went bad. I did a scan of my car recently with an X431 Launch EasyDiag, had an error message for one of the passenger footwell temperature sensors. Haven't fixed it yet because I don't get passengers that often and none of them have complained so far. You're probably going to have to take it to the dealer to get a more definitive diagnosis.

Arrie

It is a common thing that the system loses charge due to a leak but equally it stops working if it is overcharged so check that the system is not overcharged.

AnirInTexas

Just reading this tread. My car is in the shop as we speak to replace the compressor and the dryer. My issue why i took the car in the first place, was that 3 out of 10 times when you turn the AC on you will just get outside air. you had to either wait 10 minutes or keep turning it on or off until it kicked in. I have extended warranty so they sent an inspector to check it. He asked the dealer to evac and charge it again which they did and problem still was there. So they agreed to replace them.

Rocman8

a weird issue that stumps a lot of people with these intermittent ac not cold concern is sometimes the low side ac line off the compressor collapses internally causing a restriction. only way to know for sure is to disconnect it and go in with a borescope. ive seen a few of these and always after someone has replaced a bunch of parts.

lightfytr

I have the same issue, not very often but every now and then. I was pissed one day it was so hot and I went out to get the car running and cool off. Came back out 5 minutes later and it was like a sauna in there. Had to turn the car on and off and it got cold. im just dealing with it as well. I rather this for now than pay a grand to fix it. Rather wait until it breaks.

mellonc

isn't there an air mix servo (motor) that mixes hot and cold air coming out? that seems to be the first to go in an auto climate system usually.....

Rocman8

Yes there is but they are very uncommon to fail on Mercedes but you never know which is why it's a must to have the car scanned with a DAS star system and a proper diagnosis before throwing parts at it.

LILBENZ230

I thought it was common to only get 6-7 years out of MB A/C compressors? Mine went out at 7 years on my W203 and at 6 years on my 09 W204. They run continuously (unlike other cars where they clutch in/out) and wear out. At least that is what I was told.