What could be the cause of my A/C blowing hot heated air on the drivers side & cool, A/C air on the passenger side?

My A/C blows hot, heated air on the drivers side & cool, A/C air on the passenger side. It
also blows the same way for the rear A/C. How could I fix this problem myself? Is it the
blend doors, how do I get to them? It has R134A. The low side port tube runs cold, the
high side is hot, is this normal? Any help would be greatly appreciated.