My '99 Blazer has the full auto climate control. A previous owner replaced the blend door actuator as the original had failed.

However ever since I've owned the vehicle the heater temperature control has worked backward - cold is hot and hot is cold. And there doesn't appear to be anything inbetween full hot and full cold.

I've pulled the fuse and allowed the motor to reference itself - you can hear the motor working.

Is this a case of the motor being fitted incorrectly, or the wrong motor?