heater problem

hi im new here and i have a 02 monte carlo ss it has the dual zone heat the problem i have is no matter where i put teh driver side slider the ac and heat both blow warm well the passenger side is cold on ac and hot on heat dose anyone know what would cause this? and how to fix it?

Welcome to your first post on AF.
The heater and air cond is controlled by the body computer.
You need to start with a body/engine capable scanner and check for body pcm codes the U---- codes and also eng codes the P---- codes.
Post back codes.
Also here is a link to all data DIY repair info online sub. 24.95$ year that has good repair info on it.
http://www.alldata.com/products/diy/index.html