Inertia Fuel Shutoff Switch: Description and Operation

Inertia Fuel Shutoff Switch:

WARNING: Do not reset the Inertia Fuel Shutoff (IFS) switch until the entire fuel system has been inspected for leaks.

The purpose of the inertia fuel shutoff switch is to shut off the fuel pump in the event of a collision. 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 ramp and strikes a target plate. This opens the electrical contacts of the switch and shuts off the fuel pump. Once the switch is open, it must be manually reset before restarting the vehicle.