[tim71]

Thanks for the info. I need to study the 2nd diagram. What I was trying to accomplish was to see if the switch in the ac box below the dash was operating correctly. On the diagram it is called a thermatic switch. It is directly connected to an ac cable and lever. Maybe this switch can measure the air temperature in the cold air box, but there is no way it can detect the state of your refrigerant charge. I need to learn more about this switch.