Conventional Ignition Switch System: Start

When the ignition switch is in the START position, the switch routes voltage through the ON-designated circuitry to the BCM and a separate circuit to the PCM to start the vehicle. The circuit designated for the START mode is only used for vehicle starting.

While the engine is cranking, the BCM inhibits the accessory delay relay. After the vehicle starts, the BCM activates the accessory delay relay.

The PCM uses the ignition switch START input to determine when to activate the starter motor relay. For information on the starting system, Refer to the appropriate Engine article for the procedure.