Selecting the operating mode
Button:allows you to choose between differ-
ent operating modes.
XPress button :to change the operating
mode.
The operating mode selected appears in the
instrument cluster (
Ypage 245).
If it is not possible to change operating
modes, the display message Change the
current drive program before chang‐ing the operating mode.orExit man‐ualdriveprogramMbeforechangingthe operating mode.appears in the multi-
function display. Further information on "Dis-
play messages" (
Ypage 299).
:Operating mode selected
;Operating mode unavailable
=Operating mode available
HYBRIDRElectric mode or driving
with the internal combus-
tion engine is possible
RAutomatic selection of
drive mode with electric
mode as often as possi-
ble
RThe high-voltage battery
is discharged to approx-
imately 15%.
RTo subsequently main-
tain the condition of
charge of the high-volt-
age battery, the electric
output is reduced. All
vehicle functions such as
electric mode, energy
recuperation or boost
mode, for example, are
still available.
E-MODERPurely electric operation
until the performance
limit of the electric motor is reached
E-SAVERElectric mode or driving
with the internal combus-
tion engine is possible
RAutomatic selection of
drive mode with electric
mode as often as possi-
ble
RThe current condition of
charge of the high-volt-
age battery is maintained
so the electrical energy
can be used at a later
time.
CHARGERElectric drive is not pos-
sible
RCharging the high-volt-
age battery while driving
using the combustion
engine
In the Sport drive program (Ypage 251) and
during manual gearshifting (Ypage 251), only
the HYBRID operating mode is available.
If you switch from the Sportdrive program to
the Comfort drive program, the HYBRIDoper-
ating mode remains selected.
246PLUG-IN HYBRID operation
Driving and parking
Driving using theinternal combustion
engin eand charging th ehigh-voltage bat -
tery
The engin epowers th evehicle. The engin ealso
powers th eelectric motor. The electric motor
operates as agenerator. The high-voltag ebat -
tery is bein gcharged.
The arrows fo rth eenerg yflo ware shown in
white.
Driving using th einternal combustion
engin eand discharging th ehigh-voltage
battery
The engin epowers th evehicle. If th evehicl eis
approachin g adownhill gradien twit h a high
potential fo renerg yrecuperation ,th econdition
of charg eof th ehigh-voltag ebattery is inten-
tionally kept low or intentionally reduced.
The arrows fo rth eenerg yflo ware shown in
white.
Further information on th eroute-based operat -
in g strategy (
Ypage 253).
Electricoperation mode
The electric motor powers th evehicle. The high-
voltag ebattery supplies energ yto th eelectric
motor.
The arrows fo rth eenerg yflo ware shown in
green .
Electri coperation mode and charging th e
high-voltage batter y
The electric motor is operatin gas agenerator,
e.g. in overrun mod eand when braking. The
kineti cenerg yof th evehicl eis converted into
electrica lenergy. The high-voltag ebattery is
bein gcharged.
The arrows fo rth eenerg yflo ware shown in
green .
PLUG-IN HYBRID operation249
Driving and parking
Z
Activating when driving with the electric motor:
XPull the left or right steering wheel paddle
shifter (Ypage 159).
The combustion engine is switched on. Man-
ual gearshifting is activated temporarily. The
selected gear and Mappear in the multifunc-
tion display.
Activating when driving with the combustion
engine:
XPull the left or right steering wheel paddle
shifter (Ypage 159).
Manual gearshifting is activated temporarily.
The selected gear and Mappear in the multi-
function display.
The ECO start/stop function is not available
when manually changing gear.
For further information on the manual drive pro-
gram (
Ypage 159).
Driving tips
General driving tips
Drive carefully and maintain a safe distance
from the vehicle in front. Avoid frequent and
sudden acceleration as well as abrupt braking.
During partial electric driving, pulling away and
acceleration, the electric motor supports the
internal combustion engine.
During overrun in transmission position Dand
braking, the electric motor will operate as a gen-
erator.
Further information on the ECO start/stop func-
tion (
Ypage 253).
Additional driving tips (
Ypage 181).
Stationary vehicle
If the vehicle is stopped, the combustion engine
is, for the most part, switched off. Automatic
climate control continues to function. The elec-
tromechanically assisted steering gear allows
you to use the power steering without reduced
comfort.
Acceleration
Depending on the operating mode, pulling away
and driving under low load conditions are per-
formed:
Rentirely by electric propulsion
Rin combination with the internal combustion
engine When accelerating rapidly under increased or
full load, increased boost mode is utilized. The
electric motor supports the combustion engine
by providing additional drive torque.
Overrun mode or braking
There are three possible operating modes when
the hybrid vehicle is decelerating:
Renergy recovery takes place even when the
vehicle is decelerating purely in overrun mode
(
Ypage 242). The electric motor operates as
a generator and stores the recovered energy
in the high-voltage battery.
Rwhen the brakes are applied lightly, the vehi-
cle is slowed down further by the electric
motor. This increases the energy recovery
taking place (
Ypage 242). The electric motor
operates as a generator and stores the recov- ered energy in the high-voltage battery.
Rwhen the brakes are applied with greater
force, the service brakes are also used to slow
the vehicle down. The two systems work
together.
Urban driving
In city traffic, energy is recuperated during fre-
quent deceleration phases.
The vehicle can be driven by the electric motor
alone up to a speed of approximately 80 mph
(130 km/h).
The vehicle is driven by the electric motor alone
only when all conditions for the automatic
engine switch-off are fulfilled.
Further information on the automatic engine
switch-off (
Ypage 253).
Driving on inter-urban roads
The following phases are possible when driving
on inter-urban roads:
Rrapid acceleration (boost mode)
Renergy recuperation
Relectric operation mode
The vehicle can be driven by the electric motor
alone up to a speed of approximately 74 mph
(120 km/h).
A great deal of recovered energy may be avail-
able, depending on the route profile. This
reduces consumption and emissions.
252PLUG-IN HYBRID operation
Driving an d parking
Problems with PLUG-IN HYBRID operation
Internal combustion engine
ProblemPossible causes/consequences and MSolutions
You cannot start the
internal combustion
engine. The multifunc-
tion display shows no
display messages. The
READY indicator in the
multifunction display is
off.For example, self-diagnosis is not yet complete or the hybrid drive
system is malfunctioning.
XSwitch off the ignition and turn it back on.
XTry to start the internal combustion engine again.
If the internal combustion engine still does not start:
XConsult a qualified specialist workshop.
You wish to pull away,
but the ECO start/stop
function does not start
the internal combustion
engine. The READY indi-
cator in the multifunc-
tion display is off.The ECO start/stop function has failed. The warning and indicator
lamps in the instrument cluster light up.
XShift the transmission to P.
XSwitch off the ignition and turn it back on.
XStart the engine.
The hybrid drive system is faulty.
XConsult a qualified specialist workshop.
Recuperative Brake System
ProblemPossible causes/consequences and MSolutions
Braking resistance is
reduced and brake pedal
travel is longer than
usual.GRisk of accident
The Recuperative Brake System is malfunctioning.
XObserve the additional display messages in the multifunction dis-
play (Ypage 280).
XObserve the information regarding indicator and warning lamps in
the instrument cluster (Ypage 318) .
PLUG-IN HYBRID operation255
Driving and parking
Z
Hybrid drive system
ProblemPossible causes/consequences andMSolutions
The hybrid drive system
has been switched off
automatically.You have been in an accident.
The hybrid drive system remains switched off if:
Rthe internal combustion engine cannot be restarted after a few
seconds.
Rthe red6restraint system warning lamp in the instrument clus-
ter is lit.
XConsult a qualified specialist workshop.
The hybrid drive system
has been switched off
automatically. The multi-
function display also
shows a display mes-
sage.An electrical short circuit has occurred in the hybrid drive system or an
electrical connection has been disconnected.
XObserve the additional display messages in the multifunction dis-
play (Ypage 280).
XConsult a qualified specialist workshop.
Towing a trailer
Important safety notes
GWARNING
Installing an unsuitable ball coupling may
result in overloading of the trailer tow hitch
and the rear axle. This applies especially if the ball coupling in question is longer or angled
differently. This could seriously impair the
driving characteristics and the trailer can
come loose. There is a risk of an accident.
You should only ever install a ball coupling
that has the permissible dimensions and that
is designed to meet your trailer-towing
requirements. Do not modify the ball coupling
or the trailer tow hitch.
You will find the values approved by the manu-
facturer on the vehicle identification plates and
those for the towing vehicle under "Technical
data" (
Ypage 445).
GWARNING
If the ball coupling is not installed correctly or not secured with the bolt provided and the
corresponding spring cotter, the trailer may
come loose. There is a risk of an accident.
Always install and secure the ball coupling as
described. Before every journey, ensure that
the ball coupling is secured with the bolt and
the corresponding spring cotter.
GWARNING
When the vehicle/trailer combination begins
to lurch, you could lose control of it. The vehi- cle/trailer combination could even rollover.
There is a risk of an accident.
On no account should you attempt to
straighten up the vehicle/trailer combination
by increasing the speed. Reduce vehicle
speed and do not countersteer. Apply the
brake as necessary.
Please observe the manufacturer's operating
instructions for the trailer coupling if a detach-
able trailer coupling is used.
Couple and uncouple the trailer carefully. If you
do not couple the trailer to the towing vehicle
correctly, the trailer could become detached.
Make sure that the following values are not
exceeded:
Rthe permissible trailer drawbar noseweight
Rthe permissible trailer load
Rthe permissible rear axle load of the towing
vehicle
Rthe maximum permissible gross vehicle
weight of both the towing vehicle and the
trailer
256Towing a trailer
Driving and parking
tem and prevents the brakes from overheating
and wearing too quickly. If you need additional
braking, depress the brake pedal repeatedly
rather than continuously.
Driving tips
If the trailer swings from side to side:
XDo not accelerate.
XDo not counter-steer.
XBrake if necessary.
RMaintain a greater distance from the vehicle
in front than when driving without a trailer.
RAvoid braking abruptly. If possible, brake gen-tly at first to allow the trailer to run on. Then,
increase the braking force rapidly.
RThe values given for gradient-climbing capa-
bilities from a standstill refer to sea level.
When driving in mountainous areas, note that
the power output of the engine and, conse-
quently, the vehicle's gradient-climbing capa-
bility, decreases with increasing altitude.
Installing the ball coupling
GWARNING
If the ball coupling is not correctly installed
and secured, it can come loose during the
journey and endanger other road users. There is a risk of an accident and injury.
Always install and secure the ball coupling as
described. Before every journey, ensure that
the ball coupling is secured with the bolt and
the corresponding spring cotter.
GWARNING
If the ball coupling is not installed correctly or not secured with the bolt provided and the
corresponding spring cotter, the trailer may
come loose. There is a risk of an accident.
Always install and secure the ball coupling as
described. Before every journey, ensure that
the ball coupling is secured with the bolt and
the corresponding spring cotter.
GWARNING
If the ball coupling is not installed and secured
correctly the trailer may come loose. There is
a risk of an accident.
Install and secure the ball coupling as descri-
bed in the ball coupling installation instruc-
tions. Make sure that the ball coupling is
installed and secured correctly before every
journey.
XPull protective cap :in the direction of the
arrow, out of the ball coupling recess.
XStow protective cap :so that it cannot be
thrown around.
Observe the loading guidelines (
Ypage 329)
and the safety notes regarding stowage
spaces (
Ypage 330).
258Towing a trailer
Driving an d parking
XInsert the ball coupling horizontally into ball
coupling recess;in the direction of the
arrow until the holes in ball coupling =are in
line with the holes in ball coupling recess ?.
XSlide boltAinto the hole in the ball coupling
recess and the ball coupling to the stop.
XSecure the bolt using spring cotter B.
XCheck the ball coupling, bolt and spring cotter
for correct installation.
If the ball coupling cannot be correctly mounted,
remove the ball coupling. Under these circum-
stances, the ball coupling must not be used for
trailer towing.
Have the entire trailer tow hitch checked at a
qualified specialist workshop.
Coupling up a trailer
!
Do not connect the trailer's brake system (if
featured) to the hydraulic brake system of the
towing vehicle, as the latter is equipped with
an anti-lock brake system. Doing so will result
in a loss of function of the brake systems of
both the vehicle and the trailer.
XShift the transmission to position P.
XApply the vehicle's electric parking brake.
XStart the engine.
XVehicles with AIRMATIC package: select
normal level and the Comfortdrive program.
XSwitch off the engine.
XClose the doors and tailgate.
XCouple up the trailer.
Towing a trailer259
Driving and parking
Z
XEstablish the electrical connection between
the vehicle and the trailer.
XCheck that the trailer lighting system is work-
ing.
XPush the combination switch upwards/down-wards and check whether the corresponding
turn signal on the trailer flashes.
A trailer that is connected is recognized only
when the electrical connection is established
correctly and when the lighting system is work-
ing properly. The function of other systems also
depends on this, for example:
RESP®
RPARKTRONIC
RActive Parking Assist
RActive Blind Spot Assist
RActive Lane Keeping Assist
iVehicles with the AIRMATIC package: if you
couple up a trailer, the vehicle always remains
at normal level. When coupling up a trailer,
please observe the following:
RIf the normal level has not been set man-
ually, the vehicle is automatically lowered
to normal level. This is the case if a speed of
5 mph (8 km/h) is reached.
RThe Sport drive program is not available.
These restrictions apply to all accessories
powered through a connection to the trailer
power socket of your vehicle, e.g. a bicycle
carrier.
Observe the maximum permissible trailer
dimensions (width and leng
th).
Most U.S. states and all Canadian provinces
require by law:
RSafety chains between the towing vehicle and
the trailer. The chains should be cross-wound
under the trailer drawbar. They must be fas-
tened to the vehicle's trailer coupling, not to
the bumper or the axle.
Leave enough play in the chains to make tight
cornering possible.
RA separate brake system for certain types of
trailer.
RSafety switch for braked trailers. Check the
specific legal requirements applicable to your
state.
If the trailer becomes detached from the tow-
ing vehicle, the safety switch applies the
trailer brakes.
Towing a trailer
There are numerous legal requirements con-
cerning the towing of a trailer, e.g. speed restric- tions. Make sure that your car/trailer combina-
tion complies with the local regulations:
Rin your place of residence
Rin the location to which you are driving
The police and local authorities can provide reli- able information.
Observe the following when towing a trailer:
RTo gain driving experience and to become
accustomed to the new handling characteris-
tics, you should practice the following in a
traffic-free location:
-cornering
-stopping
-backing up
RBefore driving, check:
-trailer tow hitch
-safety switch for braked trailers
-safety chains
-electrical connections
-lights
-wheels
RAdjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
RIf the trailer has electronically controlled
brakes, pull away carefully. Brake manually
using the brake controller and check whether
the brakes function correctly.
RSecure any objects on the trailer to prevent
the cargo from slipping when the vehicle is in
motion.
RWhen you couple up a trailer, check at regular
intervals that the load is firmly secured. If the
tra
iler is equipped with trailer lights and
brakes, check the trailer to ensure that these
are working.
RBear in mind that the handling will be less
stable when towing a trailer than when driving
without one. Avoid sudden steering move-
ments.
RThe vehicle/trailer combination is heavier,
accelerates more slowly, has a decreased
gradient climbing capability and a longer
braking distance.
It is more susceptible to side winds and
requires more careful steering.
260Towing a trailer
Driving an d parking