Inertia Switch Test
Push down on reset button to make sure switch is closed. With fuel pump running, use DVOM to measure voltage across both terminals of inertia switch. If voltage is greater than 0.3 volts, replace inertia switch.
NOTE:
In closed position, button can be depressed an additional 1/16" against spring. This is normal and does not effect switch operation.
On Crown Victoria and Grand Marquis station wagon models, switch is located in left rear side storage compartment. On Mustang, it is located near left taillight. On Taurus and Sable station wagon models, switch is located behind access door in right rear cargo area. On all other vehicles, inertia switch is located in trunk, on left hinge support or behind trim panel.