Hello All,
Someone please help me. I have a 1995 S320 LWD, 140 body. Am having trouble with the hvac system. I am getting cool air from the left (drivers side) vents and hot air from the right side (passenger side) vents. How should I go about diagnosing this problem. Is it likely to be the push button control module, vacuum distribution block, switchover valve or something else.

 

I had the same problem, it is the climate control as you stated. Yours can be rebuilt on an exchange basis with Performance Analysis Co. 865-9175, it is about $300.00 as I remember. Do Not buy a used replacement as the control is specific to the Vin #, you have to have the correct unit or it will not work, don't ask how I know this. Your rebuilt unit will have to be programed to your car by someone that can provide this service. You will need to make a couple of release tabs to get your old unit out of the dash, they have to fit in the little slots in the face.
Steve