One morning my A/C was blowing warm air. presently the a/C would stop cooling at idle and would resume cooling as I began to drive. So I took. it to my mechanic assuming that was perhaps a leak in the evaporator or something like that. Turns out that the car refrigerant charge is full and the problem seems that the A/C clutch is not receiving any electrical feed. They have had no luck so far

Is there any sensor in the cabin or anywhere that I could check, perhaps there are overlooking something

 

The dashboard temp control unit failed on our GLK(X204) which uses the same component as the the C Class (W204).
Maybe it’s that ???
Used good temp control units are inexpensive on eBay.

 

Yes, I was just looking into that, either the cabin Temperature Sensor or the A/C Pressure Sensor located somewhere in the engine bay.

What was the problem that you had with your GLK?

 

A/C charge ok, but warm air out of vents. I scanned it and didn’t get any HVAC codes. So the system thinks everything is OK. Head scratcher.

My wife noticed that the lights on one of the dials were not moving when the dial was turned. They were on, but not moving. I pulled the one out of my C Class and everything worked fine. Diagnosis complete. Went to eBay and bought a used one.

If that turns out to be your problem, the ones without the interior color face plates were a lot cheaper 2 years ago.

BTW - Your shop should have scanned it. There are a number of sensors: inside air, outside air, refrigerant pressure, refrigerant temp, evaporator temp. And there are positions of all the air flow doors and a number of other things.

 

mine was doing the same thing for a while. Try manual shift and redline the engine and see if the a/c engages. Weird but worked until I had the a/c compressor replaced. Mine was low on refrigerant though too, they updated one of the hose designs that returns refrigerant because they leak so that was replaced too.