jepaul

Black 2007 CLK 350 Cabrio has problem with the climate control. The only way to get the A/C to blow cold is to get both climate controls to max cool and turn both climate buttons to the lowest setting. Any other position blows hot air only not mixed nor does it cycle though any fan speed changes. I thought the system was supposed to be able to maintain any temp I choose and switch from cool or warn as need. Are there are things I can check and/or change to make things work again? I Tried vacuuming the vents that I believe are the sensors and srayed electronics sensor cleaner, can they be replace and what is the procedure?