want to test the switch-----remove it from the car-----with an ohmeter test for continuity between all three contacts------it should be very low ie less than one ohm-----if it passes that then do a functional test------take a small sharp pick and mount it in a vise pointing up-----the tip must be small enough to fit into the small hole at the tip of the switch------for safety don't let it protrude more than about 1/8 inch out of the vice-------place the ohmeter across the b and c terminals and place the switch over the pick so that the sharp point is inserted into the small hole------press the switch firmly down on the pick point and the connection between contacts b and c should open with about 25 pounds of pressure------movement of the switch diaphragm will be less than 1/16 of an inch-----if that passes next do it with the a and b terminals------these contacts should open at about 40 lbs------if you can't tell the actual force used you can cut a short piece off of a pick and mount it in a block of wood----then you can sit it on a bathroom scale and read the amount of force needed to open each of the internal switches-------note------this will only work with the grey switch-----do not try this with an original black switch................RC