2001 V40 Climate control

[tkeysjr]

I have a 2001 V40, the temp selector knob will not regulate the Hot and cold temp. The fan works fine as does the air outlet setting. I use to be able to hit the panel of the controls, and the temp would change. with it being summer, the AC works fine. Getting ready for winter, can not get it to change over to heat. Any fix for this?