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Power Mode Description and Operation

Power to many of this vehicles circuits is controlled by the module that is designated the power mode master. This vehicles power mode master is the body control module (BCM). The power button switch is a low-current push button switch with discrete power button switch signals to the power mode master for determination of the power mode that will be sent over the serial data circuits to the other modules that need this information. The power mode master will also activate relays and other direct outputs of the power mode master as needed. The power mode master determines which power mode (Vehicle Off, Vehicle On, Vehicle in Service Mode) is required and reports this information to other modules via serial data. Modules which have switched voltage inputs may operate in a default mode if the power mode serial data message does not match what the individual module can see from its own connections.

The power mode master receives power button switch signals and transmitter in range signals to identify the operators desired power mode. The Power Mode Parameters table below illustrates the correct state of these input parameters (circuits) in correspondence to the power button switch position and the transmitter to vehicle range:

The BCM uses the discrete power button switch inputs, transmitter in range status, current power mode state and the brake pedal position state to distinguish the correct power mode (Vehicle Off, Vehicle On and Vehicle in Service Mode). The BCM, after determining the desired power mode, will activate the appropriate relays for that power mode and send the power mode message out to other modules in a serial data message.

The retained accessory power relay remains on for a timed period after the power mode transitions to Vehicle Off. Refer to Retained Accessory Power Description and Operation for more information on the retained accessory power function.

The vehicle has an electronic push button start switch. The power button switch is equipped with two blue LED's, one for backlighting and one for Vehicle On indication or Vehicle In Service Mode indication. The power button switch light flashes when the driver door is open and the vehicle is not on. The flashing light will eventually time out. The power button switch light is on steady when in Vehicle On or Vehicle In Service Mode. When the vehicle is turned off, the power button switch light will turn off.

This position is for driving and starting. The Vehicle On mode will be used for service (including maintenance and lubrication) and diagnostics on the electronic propulsion system or the gas engine. With the vehicle off, and the brake pedal applied, pressing the power button switch once will place the vehicle in Vehicle On mode. The instrument cluster displays an active fuel or battery gauge, along with an audio start-up cue, when the vehicle is ready to be driven. This could take up to 15 seconds at extremely cold temperatures. The gas engine will only start if needed. If the vehicle did not start, the instrument cluster will display a screen with inactive fuel and battery gauges. The electric propulsion system is active in this power mode. The gas engine will start if the bonnet is opened while in this power mode. The vehicle can be charged while in this power mode.

Note: The vehicle will not charge if the charging cable is attached to the vehicle after being placed into the Vehicle In Service Mode. Attach the charging cable to the vehicle before entering the Vehicle In Service Mode to charge the vehicle.

This power mode is available for service and diagnostics, and to verify the proper operation of the MIL as may be required for emission inspection purposes. The Vehicle In Service Mode will be used for service and diagnostics for items not requiring the electronic propulsion to be active or the operation of the gas engine. With the vehicle off, and the brake pedal not applied, pressing and holding the power button switch for more than 5 seconds will place the vehicle in Vehicle In Service Mode. The instruments and audio systems will operate as they do in Vehicle On mode, but the vehicle will not be able to be driven. The electric propulsion system is inactive in this power mode. The gas engine will not start if the bonnet is opened while in this power mode. The vehicle can only be charged in this power mode if the charging cable is attached before this power mode is enabled.

To turn the vehicle off, push the power button switch with the vehicle in P (Park). Retained Accessory Power (RAP) will remain active until the driver door is opened. Refer to Retained Accessory Power Description and Operation for more information on the retained accessory power function. When turning off the vehicle, if the vehicle is not in P (Park), the SHIFT TO PARK message is displayed in the Driver Information Centre (DIC). The electric propulsion system is inactive in this power mode. The gas engine will not start if the bonnet is opened in this power mode. The vehicle can be charged while in this power mode.

The battery saver mode reduces the parasitic load of some modules during overseas shipment or during vehicle storage conditions. This improves the drain time on the battery (up to 70 days without the battery going dead). When the vehicle is in transport/storage, some features may have reduced functionality while in the battery saver mode, such as disabling the Remote Function Actuator or content theft features.

The battery saver mode incorporates a latching relay that when enabled disconnects some modules from their ignition power or memory power sources. Battery saver mode is initiated by turning on the hazard flashers, placing the vehicle in Vehicle On mode, and then pushing the power button switch for greater than 15 seconds. The mode is disengaged by repeating the previous process causing the relay to latch in the other direction. Once the vehicle is in Vehicle On mode and the hazard flashers are on, pushing the power button switch for more than 15 seconds will latch the relay in the other direction. This feature can be used as many times as necessary if the vehicle is to be stored for an extended period of time.

The BCM is able to control or perform all of the BCM functions in the awake state. The BCM enters the sleep state when active control or normal monitoring of system functions has stopped and a time limit has passed. The BCM must detect certain wake-up inputs before entering the awake state. The BCM monitors for these inputs during the sleep state.

The BCM will enter the awake state if any of the following wake-up inputs are detected:

The BCM will enter a sleep state when all of the following conditions exist:

If all these conditions are met, the BCM will enter a low power or sleep condition.

Control modules on the serial data wake-up circuit enable or disable communication based on the voltage level of this circuit.