They are typically used in older vehicles with mechanical fuel pumps. The switch is typically located on the carburetor or fuel injection system. When the engine is running, the switch is closed and the fuel pump is turned on. When the engine is stopped, the switch opens and the fuel pump is turned off.
They can fail over time, causing the fuel pump to run constantly or not run at all. If you are having problems with your fuel pump, it is important to check the Old Style Pump Shift Switch (NC) to see if it is working properly.
To test, disconnect the switch from the electrical wiring. Then, use a multimeter to check the continuity of the switch.
If the Old Style Pump Shift Switch (NC) is not working properly, it will need to be replaced. Be sure to purchase a replacement switch that is specifically designed for your vehicle.