Highway driving
When driving on a highway, switching off the
combustion engine has a particularly positive
effect on fuel consumption and emissions.
If the driver removes his/her foot from the
accelerator pedal in theComfortdrive program
and a speed of 80 mph (130 km/h) is not excee-
ded, the combustion engine is automatically
switched off.
Further information on the automatic engine
switch-off (
Ypage 253).
ECO start/stop function
General notes
The ECO start/stop function switches the com-
bustion engine off automatically when the vehi-
cle stops moving and at speeds below 80 mph
(130 km/h) (
Ypage 253).
All vehicle systems remain active, e.g. the auto-
matic climate control.
The ECO start/stop function is neither available
in the Sport drive program nor during manual
shifting.
Automatic engine switch-off
The engine is switched off automatically, includ-
ing when:
Rthe driver removes his/her foot from the
accelerator in the Comfortdrive program and
a speed of 80 mph (130 km/h) is not excee-
ded (
Ypage 253)
Rthe engine has reached its operating temper-
ature
Rthe driver’s seat belt is fastened and the
driver’s door is closed
Rthe driver only slightly depresses the accel-
erator pedal in order to, for example, maintain
the current speed for a limited distance
Rthe hood is closed and engaged properly
Rthe high-voltage battery is charged suffi-
ciently
Rno malfunctions are present in the hybrid
drive system
The internal combustion engine will not be
switched off automatically, if:
Rthe self-diagnosis function of the engine man-
agement is active
Rthere is a malfunction in the hybrid drive sys-
tem
Rthe climate control of the vehicle requires it
Rthe high-voltage battery is being charged
(Ypage 248)
Automatic engine start
The automatically switched-off internal combus-
tion engine starts automatically in certain situa-
tions, if:
Rthe power demand from the driver via the
accelerator pedal is greater than the electric
motor alone can provide
Rthe driver switches to the Sportdrive pro-
gram or to manual gearshifting
Rthe condition of charge of the high-voltage
battery has reached the lower limit
Rthe driver has selected the CHARGE operating
mode
Overrun mode
In overrun mode, the combustion engine is
switched off and is disconnected from the drive
train. The electric motor:
Rgenerates low thrust, which corresponds to
the overrun mode of an active combustion
engine
Rfunctions as a generator and produces the
necessary energy for the auxiliary consumers and charges the high-voltage battery
Overrun mode is available in the Comfortdrive
program at speeds below 80 mph (130 km/h).
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:
Rroad categories
Rspeed limitations
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:
Rthe sections of the journey ahead
Rthe energy consumption on the whole route
PLUG-IN HYBRID operation253
Driving and parking
Z
Display messagesPossible causes/consequences andMSolutions
ServiceRequiredDoNot Shift GearsVisit Dealer
You canno tchang eth etransmission position due to amalfunction .
A warning tone also sounds.
If transmission position Dis selected:
XDrive to aqualified specialist workshop without shifting th etrans -
mission from position D.
If transmission position R,N or Pis selected:
XSecur eth evehicl eagainst rollin gaway (Ypage 178).
XNotify aqualified specialist workshop or breakdown service.
ReversingNotPossi‐bleServic eRequiredYou canno tshift int oth etransmission position Rdue to amalfunction .
The transmission position sP,N or Dcontinu eto be available.
A warning tone also sounds.
XVisit aqualified specialist workshop .
Transmission Mal‐function StopAmalfunction has occurred in th emechanical transmission compo -
nents.
A warning tone also sounds. The gearbox automatically shift sto posi-
tion N.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XShift th etransmission to position P.
XSecureth evehicl eagainst rollin gaway (Ypage 178).
XNotify aqualified specialist workshop or breakdown service.
Sto pVehicl eLeaveEngineRunnin gWaitTransmission Cool‐ing
PLUG-I NHYBRID vehicles:
The transmission has overheated. Pullin gaway can be temporarily
impaire dor no tpossible.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions. Do no tcontinu edrivin g
under any circumstances.
XWait until th edisplay message disappear sbefore pullin gaway.
Auxiliary Batter yMalfunctionThe auxiliary battery for th eautomatic transmission is no longer bein g
charged.
XVisit aqualified specialist workshop .
XUntilthen ,set th eautomatic transmission to position Pbefore you
switch off th eengine.
XBefor eleaving th evehicle, apply th eelectric parking brake.
AThe tailgat eis open .
GWARNIN G
Whe nth eengin eis running, exhaust gase scan ente rth evehicl einte-
rio rif th etailgat eis open .
There is aris kof poisoning .
XCloseth etailgate.
312Display messages
On-board computer and displays