FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Ignition Switch: Description and Operation: Overview




Conventional Ignition Switch - without Intelligent Access (IA)

Overview

The conventional ignition switch is controlled by the ignition lock cylinder and key. The ignition lock cylinder and ignition switch are connected mechanically, turning the lock cylinder places the switch into the desired position. The available ignition switch positions are:
- OFF
- ACC
- RUN
- START

When placed in any position other than OFF, the ignition switch provides voltage inputs to the BCM (Body Control Module). The BCM (Body Control Module) distributes this voltage to other modules and vehicle systems through the RUN/ACC and the RUN/START relays. The microprocessor internal to the BCM (Body Control Module) broadcasts an ignition mode network message over the MS-CAN (Medium Speed Controller Area Network) and the HS-CAN (High Speed Controller Area Network).