switch on 1991 Mercury Tracer

what is an inertia switch

Asked by for the 1991 Mercury Tracer
An inertia switch is a safety device that interrupts power to the fuel pump/ cuts off fuel delivery in the case in which the car is involved in an accident. Many cars fitted with an inertia switch experience failure for no apparent reason. They usually have a reset button on top similar to a reset button on a household circuit breaker.