190 e 2.3 heat issues

[mullan27]

Guys, i have seen this topic covered in this forum for other models but cant seem to find anyone having the problem on the 190(although i am a computer moron).
The heat is always coming out of the defroster in my merc, the fan control works and i can adjust the fan speed but i can never shut the heat off.
The vents work when i switch to them so its not a "vacuum" problem that i see mentioned so often. The A/C no longer works either. Is there a problem with the ECU or is it somewhere else? Any help woulb be greatly appreciated