Operation Manual

Automatic engine start
The automatically switched-off internal combus-
tion engine starts automatically in certain situa-
tions, if:
R
the power demand from the driver via the
accelerator pedal is greater than the electric
motor alone can provide
R
the driver switches to drive program S or M
R
the condition of charge of the high-voltage
battery has reached the lower limit
R
the settings of the automatic climate control
require it, e.g. at external temperatures above
30 †
Overrun mode
In overrun mode, the combustion engine is
switched off and is disconnected from the drive
train. The electric motor:
R
generates low thrust, which corresponds to
the overrun mode of an active combustion
engine
R
functions as a generator and produces the
necessary energy for the auxiliary consumers
and charges the high-voltage battery
Overrun mode is possible in the following speed
range:
R
in drive program E below 81 mph (130 km/h)
R
in drive program E+ below 112 mph
(180 km/h)
In drive program E+, after the accelerator pedal
has been released the coasting characteristics
of the vehicle are adapted to the traffic condi-
tions. Further information about the haptic
accelerato
r p
edal (Y page 251).
Route-based operating strategy
For the route-based operating strategy, the sys-
tem factors in information about the expected
route when route guidance is active.
The information on the route is provided by the
multimedia system and includes the following:
R
road categories
R
speed limitations
R
data on downhill gradients
The use of electric energy is automatically opti-
mally distributed from the beginning to the end
of the journey, using information about the
route. The distribution is pre-emptive and takes
into consideration:
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the sections of the journey ahead
R
the energy consumption on the whole route
The condition of charge of the high-voltage bat-
tery is thus systematically controlled. In addi-
tion, the control function takes into account
that:
R
the fuel savings through the use of electrical
energy can vary, depending on the route (e.g.
urban, interurban or highway)
R
the use of electrical energy is held available in
particular for electric operation (e.g. urban
routes)
The vehicle thus automatically selects the opti-
mum driving mode for the respective section of
the route.
The route-based operating strategy is available
under the following conditions:
R
drive program E+ is selected
R
HYBRID driving mode is selected
R
active route guidance is activated
R
suitable map data is available
When the route-based operating strategy is
being used, the area in front of the vehicle is
shown as green in the multifunction display.
Parking
X
Apply the electric parking brake.
The red ! indicator lamp in the instrument
cluster lights up.
X
Use the DIRECT SELECT lever to shift the
automatic transmission to P.
X
Switch the ignition off.
The READY indicator in the instrument cluster
goes out.
Further information on parking and switching off
the internal combustion engine (
Y page 190).
PLUG‑IN HYBRID operation
253
Driving and parking
Z