Ignition Switch Off

This is an Open Loop mode. When the ignition switch is turned to the OFF position, the engine controller ceases to provide a ground for the auto shutdown (ASD) relay. It extends the ISC actuator in anticipation of the next start up. When the ASD relay is not energized, battery voltage is shut off from the fuel pump, fuel injector, ignition coil, and oxygen sensor heating element. All fuel injection stops.