"W124 Cabin Sensor"

[dablk1]

I believe that the blower that draws the air past my cabin sensor isn't working properly. The interior never maintains the correct temperature.
I was told yesterday to try the "paper test" whereas the fuctionality can be tested by tearing off a very small piece of plain paper, or even tissue paper and placing it over the vent in front of the sunroof switch above the rear view mirror and it should stay. Nevertheless the paper didn't stay.
Also on another note, while my car is idling without the climate control it maitains perfect cooling temperature. When I turn on the heat, not the a/c, the coolant temperature starts rising. Yesterday I believe that the high speed fans came on to cool the engine due to the fact that it hit 100 C. Does anyone have a clue as to what can be causing this?