The temperature control on my 03 Escape has stopped working. The control is a plastic rotary knob that is broken due to the force needed to move the temp control. Have to use pliers its so stiff. I have taken apart the control and nothing is seized or broken. There are 2 cables that go down and disappear into the dash area. Do these cables go to a heater control valve or a blend door? My guess it that is what has gone bad is the water vales, but it is buried far into the dash and out of sight.