ac problem 97 grand ltd help

I have a 97 grand limited with climate control and my problem is it heats all the time when the climate control is on . the compressor is working . it will not control the heat either you can set it to lo and it will cook you out. is there a blend door that could be broken or any thing that i can try. i think it is in the heater/evap box . any help will be apreciated Thanks:screwy:

Yep. There is a servo motor that runs the blend door and another that runs the mode doors. The blend door servo is slightly left of the transmission hump, but unfortunately I don't believe it is replaceable without moving the box (which means pulling the dash partially out).