Hybrid Modes of Operation Description

Hybrid Modes of Operation Description

Automatic Engine Start/Stop

Warning

Exiting the vehicle without first shifting into P (Park) may cause the vehicle to move. You or others may be injured. Because the vehicle has the automatic engine start/stop feature, the vehicle's engine might seem to be shut off; however, once the brake pedal is released, the engine will start up again.

Shift to P (Park) and turn
the ignition to LOCK/OFF, before exiting the vehicle.

Vehicles with eAssist have an automatic (auto) engine start/stop feature. After the engine has started and reached operating temperature the auto stop feature may cause the engine to turn off when brakes are applied and the vehicle has come to a complete stop. When the brake is released or the accelerator pedal applied, the engine will start. The engine will continue to run until the next auto stop or until the ignition switch is turned OFF.

AUTO STOP on the tachometer signifies that the engine is in auto stop mode. When the vehicle is turned off, the tachometer will move to OFF. If the driver door is opened while in auto stop mode, a chime will sound.

To restart the engine during auto stop, release the brake pedal or press the accelerator pedal. The engine starts immediately. The engine continues to run until the next stop.

There are several conditions which may prevent an auto stop or cause an auto start.

The Engine Will Remain Running When:

* The engine, transmission, or hybrid battery is not warmed up.

* The outside temperature is less than -15°C (5°F).

* The air conditioning or defrost system requires the A/C compressor to maintain vehicle comfort.

* The shift lever is in any position other than DRIVE.

* The hybrid battery pack charge is low.

* The 12-volt vehicle battery charge is low, or loads are high.

* The hood is not fully closed.

The Engine Will Restart When:

* The brake pedal is released.

* The accelerator pedal is applied.

* Shifting out of D (Drive) to any other gear.

* If the eco air conditioning button is selected, the duration of the auto stop will mainly depend on the outside temperature along with some other factors. This economy mode improves fuel economy by limiting the effects of the air conditioning. The warmer it is outside, the shorter the time before the engine is restarted to provide cabin cooling.

* The climate control system is turned from off to normal air conditioning or defrost.

* The engine is required to run for either heater or climate control performance.

* The hybrid battery pack charge is low and requires recharging.

* Auto stop time is greater than two minutes.

Regenerative Braking

Regenerative braking takes some of the energy from the moving vehicle and turns it into electrical energy. This energy is then used to charge the vehicle's hybrid battery system, which increases fuel efficiency.

The torque converter stays locked allowing the drive motor to be coupled to the wheels (through engine and trans) to recharge the hybrid batteries via regenerative braking.

The system works whenever you take your foot off the accelerator pedal while the vehicle is moving in a forward gear. This causes the vehicle to slow down more quickly. It may feel like the brake pedal is being pressed, even when it is not. When the brake pedal is depressed the system will deliver a higher percent of regenerative energy to the hybrid battery system than when in coast down.

Electric Power Assist

Significant internal transmission changes to clutch controls and hardware provide reduced spin losses while improving shift quality. The added electric power provided by the eAssist system allows for higher gearing to improve steady state efficiency without impacting acceleration performance or driveability. The system's capability of providing up to 11 kW of electric power assist at cruising speeds allows the driver to accelerate lightly, ascend mild grades without the transmission downshifting and helps performance during wide open throttle maneuvers.

Torque Smoothing

While not unique to the eAssist hybrid vehicle, expanded operational range is possible because the drive motor can react quickly to smooth driveline disturbances that would otherwise be objectionable.

Deceleration Fuel Cut-Off

When the driver releases the accelerator pedal, air flow into the engine is reduced. The ECM monitors the corresponding changes in the throttle position, MAP, and MAF. The ECM shuts OFF fuel completely if the deceleration is very rapid, or for long periods, such as closed-throttle coast-down. The fuel shuts OFF in order to prevent damage to the catalytic converter and saves fuel by not running the engine. This mode is activated quickly and for a longer duration in the eAssist hybrid vehicle.

While in deceleration fuel cut-off mode, the torque converter stays locked allowing the drive motor to be coupled to the wheels (through engine and trans) to recharge the hybrid batteries via regenerative braking. The drive motor can also quickly react to help smooth driveline disturbances (downshifts), or provide assist for a smooth take off when the accelerator is depressed. If the vehicle is brought to a complete stop the drive motor spins the engine bringing it to a smooth stop and is properly positioned for a smooth restart.