Applies to vehicles: with hybrid drive
To switch on EV mode, press the button. The indicator lamp in the button will light up. The indicator lamp will also light up in the instrument cluster display.
The functions and driving modes described in the following are automatically selected by the vehicle's control system depending on the vehicle's current status. This ensures that the vehicle is always in the correct mode. Extended electric driving is an exception to this; it is activated by the driver Link.
Driving with the combustion engine
The vehicle is driven by the combustion engine. At the same time, the high-voltage battery is charged if required.
Full acceleration (boost)
For full acceleration, the vehicle is simultaneously driven by both the combustion engine and the electric motor. This driving mode is called boost and is only available for a short time as it uses a lot of energy. Its availability is dependent on the charge level of the high-voltage battery.
The boost function is activated when the accelerator pedal is pressed a long way down.
Electric driving
Depending on the driving conditions and the charge level of the high-voltage battery, the vehicle can be driven using only the electric motor with the combustion engine switched off.
The combustion engine is started under acceleration or if the high-voltage battery's charge is no longer sufficient. As soon as the driver does not require fast acceleration and the high-voltage battery's charge allows it, the vehicle will again run on electric power.
Extended electric driving (EV mode)
By pressing the button Fig. 1, the usual limits of electric driving can be extended and you can drive with electric power when the status of the electrical system allows this. The vehicle is then set to run on electric power as often as possible -3-, -12- Fig. 2. It is possible to drive up to 3 km at a constant speed of 60 km/h using only electric power.
The following requirements must be met for extended electric driving to be activated:
- There must be sufficient charge in the high-voltage battery.
- The 12 Volt batteries and the high-voltage battery must be at the correct temperature.
- The vehicle's speed must not be higher than approx. 100 km/h.
- The gearbox must not be set to tiptronic mode.
- Off-road mode and the downhill assist function must not be activated Link.
Extended electric driving will be interrupted and the combustion engine started when you accelerate. The grey indicator lamp will also light up in the display. Extended electric driving is resumed after acceleration is complete.
Extended electric driving is deactivated if one or more of the following occurs:
- The ignition is switched off.
- The button is pressed again.
- The charge level of the high-voltage battery is low.
- The vehicle's speed is higher than approx. 100 km/h.
- Selector lever position S or tiptronic mode is selected.
- Off-road mode or the downhill assist function are switched on.
The button must be pressed again to re-activate the system.
As long as the combustion engine has not reached its operating temperature, it is possible to drive off under electric power without the combustion engine cutting in. To do so, prepare the vehicle for driving with the selector lever in position P, press the button and then move the selector lever to D or R.
Start/stop function
The combustion engine is only used when it is needed. As a rule, the combustion engine is switched off when the vehicle is not in motion; the high-voltage battery provides the energy that the vehicle's electrical systems require.
On the hybrid system, automatically switching off the combustion engine in normal driving is intended to save fuel. All of the important vehicle systems such as the steering, the brakes and the air conditioner remain activated. In some cases, it may be necessary to also run the combustion engine when the vehicle is not moving for system reasons. On long journeys in heavy traffic, the combustion engine is switched on periodically when the vehicle is stationary in order to charge the high-voltage battery.
Coasting
The combustion engine is switched off when the selector lever is in position D, the accelerator pedal is not being pressed and the vehicle's speed is up to approx. 160 km/h. This makes it possible to reduce fuel consumption by thinking ahead.
Energy recuperation
When the vehicle brakes, electrical energy is produced by the electric motor (which is in this case working as a generator) and used to charge the high-voltage battery. This also happens if the vehicle is going downhill or is coasting in gear (overrun). In this case the combustion engine is automatically switched off.
If you brake early and smoothly with short pedal movements, the vehicle is braked by the electric motor Fig. 2 -6-. This means that a large amount of the kinetic energy can be recovered and used as electrical energy to charge the high-voltage battery. Under heavy braking, the normal brakes are also activated Fig. 2 -10-.
The amount of energy recovered is shown on the infotainment display Link.
Automatic start of combustion engine
Different operating modes lead to the combustion engine being started automatically:
- The charge level of the high-voltage battery is low.
- The combustion engine temperature is low.
- The temperature of the catalytic converter is low.
- The air conditioner requires a lot of power.
- The speed of the vehicle is high.
- Heavy acceleration is required.
- The gradient you are driving on is steep.
- The charge level of the high-voltage battery is high and the vehicle is coasting. In this case, the high-voltage battery cannot take in any more energy. This means that the electric motor cannot slow the vehicle down. The combustion engine is switched on and runs with the fuel supply interrupted (engine braking).