Network Message Chart - Push Button Start

GWM Module Network Input Messages

Broadcast Message	Originating Module	Message Purpose
Ignition status	BCM	This message informs the GWM of the current ignition status; off, accessory, run, start, unknown or invalid.

PCM Module Network Input Messages

Broadcast Message	Originating Module	Message Purpose
Ignition status	BCM	This message informs the PCM GWM BCM of the current ignition status; off, accessory, run, start, unknown or invalid.

Push Button Ignition Switch

The push button ignition switch is used to control the ON, OFF and START ignition modes.

The BCM monitors one circuit for voltage from the ignition switch and sends a voltage signal on a second circuit to the ignition switch to monitor requests to turn the ignition on, off or to start the vehicle. When the button is pressed, one circuit routes battery voltage to the BCM while the voltage signal from the BCM on the second circuit is routed to ground, indicating a request to change the ignition state. Changing the ignition state from the OFF mode works in conjunction with the PATS. A programmed key is required to change the ignition from OFF to ON. For additional PATS information, Refer to: Passive Anti-Theft System (PATS) - System Operation and Component Description .

Refer to the following table for information about achieving the various ignition states.

Ignition Entry Condition	Desired Ignition Mode	Action To Take
Off	ON (engine off)	Press the START/STOP button without applying the brake pedal.
Any ignition mode	START	Apply and the brake pedal and then press the START/STOP button.
On (engine off)	OFF	Press the START/STOP button.
On (engine running)	OFF	Press and hold the START/STOP button.

The BCM must recognize a programmed key before it changes the ignition state from OFF.

Ignition Mode LED Indicator

The ignition mode LED indicates the ignition mode of the vehicle. The BCM controls the voltage to the ignition mode LED indicator. Refer to the following table.

Ignition Mode	Ignition Mode LED Indicator
Off	Off
On (engine off)	Flashing
On (engine running)	On

OFF

The BCM controls the relays providing voltage to the vehicle electrical systems. When the ignition is in the ON mode, a single press and release of the START/STOP button changes the ignition to the OFF mode. No programmed key is required to change the ignition to the OFF mode when the vehicle is running.

If the vehicle is in motion, a momentary press of the START/STOP button does not shut the vehicle off. If the vehicle is moving, the START/STOP button must be pressed and held for longer than one second to turn the ignition off.

When the BCM changes the ignition state to OFF, it communicates the ignition mode to the other modules by sending an ignition status message over the CAN.

The BCM must recognize a programmed key before it changes the ignition state out of OFF. When the START/STOP button is pressed when the ignition is off, the BCM checks the vehicle for a programmed key as part of the PATS function. If no programmed key is detected, the ignition remains off. For additional PATS information, Refer to: Passive Anti-Theft System (PATS) - System Operation and Component Description .

When the ignition is in the ON mode, the BCM activates the run/start relays to provide voltage to the vehicle electrical systems and communicates the ignition mode to the other modules by sending an ignition status message over the CAN.

When the vehicle enters ON mode, multiple indicators in the IPC prove out and the IPC displays the gear selection and the vehicle mileage.

START

If the brake pedal is applied when the START/STOP button is pressed, the vehicle temporarily goes into the START mode so long as a programmed key is detected within the vehicle.

In addition to activating the run/start relays, the BCM communicates the ignition mode to the other modules by sending an ignition status message over the CAN.

Once the ignition has entered START mode, the indicator in the ignition switch illuminates.

The engine can be started from any ignition mode.