Circuit/System Description

WARNING: This page is about a different car, the 2010 Buick LaCrosse. However, it is still accessible from the selected car via links, so may be relevant.

The ignition mode switch has 2 LED's that indicate the vehicle power mode. When the vehicle is in the off mode, both LED's will be off. Pressing the ignition mode switch button once (without the brake pedal applied), the vehicle enters the accessory mode and the amber LED (ACC) will illuminate. Pressing the ignition mode switch button a second time (without the brake pedal applied), the vehicle enters the run/start mode (without the engine running) and the green LED (Run/Start) will illuminate. With the ignition off (with the brake pedal applied), pressing the ignition mode switch button once, the vehicle will enter run/start mode and the green LED (run/start) will illuminate. This will start the engine. Both LED's have the voltage supplied from the body control module (BCM). The ignition mode switch sends the ignition mode switch status to the keyless entry control / passive entry passive start module (PEPS) and to the BCM. The keyless entry control module sends a redundant signal to the BCM with the ignition mode switch status.