CHRYSLER PACIFICA HEATER NOT WORKING

When I Warm My Car Up In The Winter Or We Are Sitting At A Stop Light My Car Only Blows Cold Air Why? The Temp Gage Is Fine And Runs Great...

My Blower Fan Is Working Properly, My Mode Seems Stuck On Blowing Air From Dash Vents (when I Select The Mode For Foot Level And Defrost...

Heater Core Started Leaking Before It Was Parked Couple Years Ago And Everything Worked Fine Before That. Heater Core, Upper Radiator Hose...

There Is No Air Coming Out Of The Front Vents Or When I Push The Defrost Button. But There Is Air Coming Out Of The Rear Vents, But Only...