I have an 02 trailblazer with electric dual climate control the driver side works good goes cold and hot the passenger blows only cold which causes the rear vents to blow cold. NEEED help with this to figure out how to replace it without having to pay a dealership 600$.

 

Welcome to the forum. What is this "it" you want to replace and is that $600 an actual quote or just your guess?

 

If you don't know how to tear apart your dash, $600 is the way to go. There are 4 motors that cause air to be diverted from defrost, floor and vent, these motors control flaps that can get hung up or broken.