Page 28 of 52

R
During partial electric driving, pulling away
and acceleration, the electric motor
supports the internal combustio nengine.
R During overru nintransmission position D
and braking, the electric motor will operate
as a generator.
i For further information about the ECO
start/stop function (Y page 22) and driving
tips, see the vehicle Operator's Manual. Stationary vehicle
In this operating mode, the internal
combustion engine is primarily switched off.
Electric drive from the refrigerant compressor
ensures that the automatic climate control
system continues to operate. The
electromechanically assisted steering gear
allows you to use the power steering without
reduced comfort. Acceleration/boostf
unction
Depending on the drive progra mand
accelerator pedal position, the vehicle drives
in pure electric mode or in combination with
the engine .The boost function is used when
accelerating or driving at increased or full
load. The electric motor assists the engine by
providing extra torque whenever the
accelerator pedal is depressed quickly. Overrun mode or braking
When decelerating your hybrid vehicle, three
operating conditions are possible:
R energy recovery (Y page 23) takes place
even when the vehicle is decelerating
purely in overrun mode. The electric motor
operates as a generator and stores the
recovered energy in the high-voltage
battery.
R when the brakes are applied lightly, the
vehicle is slowed down further by the
electric motor. This increases the energy recovery taking place. The electric motor
operates as a generator and stores the
recovered energy in the high-voltage
battery.
R during heavy braking, the service brake is
also used to slow down the vehicle. The two
systems work together. Urban driving
The advantages of the hybrid vehicle come
especially clearly into play when driving in the
city. Energy is recovered during the vehicle's
frequent braking.
The vehicle operates exclusively with the
electric motor at speeds of up to
approximately 20 mph (35 km/h), for
example:
R while approaching a traffic light
R in stop-start traffic
i The vehicle operates exclusively with the
electric motor only if all conditions for
automatic engine switch-off are met
(Y page 22). Driving on inter-urban roads
When driving on inter-urban roads, the
vehicle switches between boost phase,
constant phase and energy recovery phase.
Ag reat deal of recovered energy may be
available, depending on the route profile. This
has a positive effect on fuel consumptio nand
emissions. Highway driving
Whe ndriving on a highway, the decrease in
wasted power through recuperatio nhas a
particularly positive effect on fuel
consumption and emissions. 26
Driving tipsDriving and parking
Page 30 of 52

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: (Y page 7).Displays and operation
Coolant temperature display
The coolan ttemperature can only be called
up on the on-board computer.
X Press =or; on the steering wheel
to select the Serv. menu.
X Press 9or: to select Coolant .
Electric motor performance display
The electric moto
rpower display in the
instrument cluster shows:
R how much of the maximum available
electric motor output is currently being
used
R how much electrical energy is being
delivered through recuperation Upper area
:shows the output obtained
from the electric motor, e.g. when driving
using the electric motor or with the boost
function. During electric drive, the engine
starts up when the display reaches the "MAX"
mark at the top. This allows you to control
how much the electric drive is used at low
speeds.
Lower area ;shows the recuperated output
which is stored in the high-voltage battery as
electrical energy. When the indicator reaches
the mark at the bottom, this means that the
recuperative braking power has been fully
utilized. The service brake is activated. Operating the on-board computer
i For information about operating the on-
board computer and COMAND, see the
vehicle Operator's Manual.
You can display the current operating mode
of the hybrid system in the multifunction
display and the COMAND display.
In the COMAND display, you can also call up
a graphic display of the fuel consumption and
generated electricity (Y page 31). Menus and submenus
Selecting
asubmenu in the
multifunction display
X Press the =or; button on the
steering wheel to select the Trip menu.
X Press 9or: to select Energy Flow .
Selecting
asubmenu in the COMAND
display
X To call up the full screen display: press
the W button.
The clock is show ninthe COMAND display
X Slide ZVthe COMAND controller up until
the Full Screen option is selected.28
Menus and submenusOn-board computer and displays
Page 35 of 52
Internal combustion engine
Display messages Possible causes/consequences and
M Solutions
~
Malfunction The hybrid system is malfunctioning.
X
Visit a qualified specialist workshop. # The battery is no
tbeing charged.
Aw arning tone also sounds.
Possible causes are:
R faulty power electronics
R a torn poly-V-belt
R a malfunction in the electronics
X Pull ove rand stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle to prevent it from rolling away.
X Ope nthe hood.
X Check whether the poly-V-belt is torn. Vehicle
Display messages Possible causes/consequences and
M Solutions
d
Malfunction The drive system is malfunctioning. The ECO start/stop function
may not be working and the vehicle may accelerate more slowly
than usual.
X Visit a qualified specialist workshop. Display messages
33On-board computer and displays
Page 36 of 52

Warning and indicator lamps in the instrument cluster
Problem Possible causes/consequences and
M Solutions
é
The yellow RBS
(recuperative
brake system)
warning lamp is
on. In addition,
there may be a
warning tone. G
Risk of accident
RBS is malfunctioning. Pedal travel may be longe rthan usual and
braking performance may be affected. The automatic engine
switch-off function may also be deactivated.
X Observe any display messages shown in the multifunction
display (Y page 31).
X Drive on carefully.
X Visit a qualified specialist workshop. $
The red brake
system warning
lamp is on. A
warning tone
also sounds. G
Risk of accident
RBS is malfunctioning. Pedal travel may be longer than usual and
braking performance may be affected.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Consult a qualified specialist workshop immediately.
X Observe the additional messages in the multifunction display
(Y page 31) (see vehicle Operator's Manual). G
Risk of accident
There is not enough brake fluid in the brake fluid reservoir.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Consult a qualified specialist workshop immediately.
X Observe the additional messages in the multifunction display
(see vehicle Operator's Manual).
Do not add brake fluid. This does not correct the malfunction. 34
Warning and indicator lamps in the instrument clusterOn-board computer and displays