What is a inertia switch

The inertia switch shuts down the fuel pump in the event of very hard braking, like in a panic stop, or in the event of a collision. This is a safety device so that if fuel is leaking as a result of a crash the risk of a fire is lessened because the fuel pump is shut off immediately. Instead of it possibly continuing to run and pumping gasoline all over the ground. Hope that helps! Jim