Inertia Fuel Shutoff Switch: Description and Operation

The inertia Switch, is used in conjunction with an electric fuel pump. The purpose of the inertia switch is to shut off the fuel pump in the event of an accident. It consists of a steel ball held in place by a magnet. When a sharp impact occurs, the ball breaks loose from the magnet, rolls up a conical ramp and strikes a target plate which opens the electrical contacts of the switch and thereby shuts off the electric fuel pump. Once the switch is open, it must be manually reset before re-starting the vehicle. The location of the switch is discussed in the owners guide.