I switch to defroster, heat is lost?

Does the air for the defroster work but no heat? Is that what you are saying? If so, I have seen the mode blend door actuator go out, but can I ask if you hear a clicking noise from under the dash? Here is the location and how to change it out in the images below. Check out the images (below). Please upload pictures or videos in your response of any problems so we can see what to help you with.