Problems with the engine
ProblemPossible causes/consequences andMSolutions
The engine does not
start. The starter motor
can be heard.RThere is a malfunction in the engine electronics.
RThere is a malfunction in the fuel supply.
Before attempting to start the engine again:
XTurn the Smartkey back to position 0in the ignition lock.
or
XPress the Start/Stop button repeatedly until all indicator lamps in
the instrument cluster go out.
XTry to start the engine again (Ypage 123). Avoid excessively long
and frequent attempts to start the engine as these will drain the
battery.
If the engine does not start after several attempts:
XConsult a qualified specialist workshop.
The engine does not
start. You cannot hear
the starter motor.The on-board voltage is too low because the battery is too weak or
discharged.
XJump-start the vehicle (Ypage 274).
If the engine does not start despite attempts to jump-start it:
XConsult a qualified specialist workshop.
The starter motor was exposed to a thermal load that was too high.
XAllow the starter motor to cool down for approximately two minutes.
XTry to start the engine again.
If the engine still does not start:
XConsult a qualified specialist workshop.
The engine is not running
smoothly and is misfir-
ing.There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
XOnly depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic converter
and damage it.
XHave the cause rectified immediately at a qualified specialist work-
shop.
The coolant temperature
gauge shows a value
above 248 ‡ (120 †).The coolant level is too low. The coolant is too hot and the engine is no
longer being cooled sufficiently.
XStop as soon as possible and allow the engine and the coolant to
cool down.
XCheck the coolant level (Ypage 256). Observe the warning notes
as you do so and add coolant if necessary.
Driving127
Driving and parking
Z
Engaging park position P automatically
Park positionPis automatically engaged if:
Ryou switch off the engine using the Smartkey
and remove the Smartkey
Ryou switch off the engine using the Smartkeyor using the Start/Stop button and open the
driver's door or front-passenger door
Rthe driver's door is opened when the vehicle is
stationary or driving at very low speed and the transmission is in position Dor R
Under certain conditions, the automatic trans-
mission shifts automatically to transmission
position Pif the HOLD function or DISTRONIC
PLUS is activated. Observe the information on
the HOLD function (
Ypage 156) and on
DISTRONIC PLUS (Ypage 150).
Engaging reverse gear R
!Only shift the automatic transmission to R
when the vehicle is stationary.
XIf the transmission is in position Dor N: push
the DIRECT SELECT lever up past the first
point of resistance.
XIf the transmission is in position P: depress
the brake pedal and push the DIRECT SELECT lever up past the first point of resistance.
The ECO start/stop function is not available
when reverse gear is engaged. Further informa-
tion on the ECO start/stop function
(
Ypage 125).
Shifting to neutral N
GWARNING
If children are left unsupervised in the vehicle,
they could:
Ropen the doors, thus endangering other
people or road users.
Rget out and disrupt traffic.
Roperate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
Rrelease the parking brake.
Rshifting the automatic transmission out of
park position P
RStart the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
XIf the transmission is in position Dor R: push
the DIRECT SELECT lever up or down to the
first point of resistance.
XIf the transmission is in position P: depress
the brake pedal and push the DIRECT SELECT
lever up or down to the first point of resist-
ance.
If you switch the engine off with the transmis-
sion in position Ror D, the automatic transmis-
sion shifts to Nautomatically.
With the Smartkey: if you then open the driv-
er's door or the front-passenger door or remove
the Smartkey from the ignition, the automatic
transmission shifts to Pautomatically.
With KEYLESS-GO: if you then open the driver's
or front-passenger door, the automatic trans-
mission shifts to P.
If you want the automatic transmission to
remain in neutral N, e.g. when having the vehicle
cleaned in an automatic car wash with a towing
system:
XVehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock.
XInsert the Smartkey into the ignition lock.
XAll vehicles: switch the ignition on.
XDepress the brake pedal and keep it
depressed.
XShift to neutral N.
XRelease the brake pedal.
XRelease the parking brake.
XSwitch off the ignition and leave the Smartkey
in the ignition lock.
Engaging drive position D
XIf the transmission is in position Ror N: push
the DIRECT SELECT lever down past the first
point of resistance.
XIf the transmission is in position P: depress
the brake pedal and push the DIRECT SELECT lever down past the first point of resistance.
Automatic transmission129
Driving and parking
Z
Transmission positions
BPark position
Only shift the transmission into posi-
tionPwhen the vehicle is stationary
(
Ypage 138). The parking lock
should not be used as a brake when
parking. Always apply the parking
brake in addition to the parking lock
in order to secure the vehicle.
If the vehicle electronics are malfunc-
tioning, the transmission may be
locked in position P. Have the vehicle
electronics checked immediately at a
qualified specialist workshop.
Park position Pis automatically
engaged if:
Ryou switch off the engine using the
Smartkey and remove the Smart-
key
Ryou switch off the engine using the
Smartkey or using the Start/Stop
button and open the driver's door
or front-passenger door
Rthe driver's door is opened when
the vehicle is stationary or driving
at very low speed and the trans-
mission is in position Dor R
CReverse gear
Only shift the transmission into posi-
tion Rwhen the vehicle is stationary.
ANeutral
Do not shift the transmission to N
while driving. Otherwise, the auto-
matic transmission could be dam-
aged.
No power is transmitted from the
engine to the drive wheels.
Releasing the brakes will allow you to
move the vehicle freely, e.g. to push
it or tow it.
If ESP
®is deactivated or faulty: shift
the transmission only to position Nif
the vehicle is in danger of skidding,
e.g. on icy roads.
If you switch the engine off with the
transmission in position Ror D, the
automatic transmission shifts to N
automatically.
!Rolling in neutral Ncan damage
the drive train.
7Drive
The automatic transmission changes
gear automatically. All forward gears
are available.
Driving tips
Changing gear
The automatic transmission shifts to the indi-
vidual gears automatically when it is in trans-
mission position D. This automatic gear shifting
behavior is determined by:
Rthe selected drive program (Ypage 131)
Rthe position of the accelerator pedal
(Ypage 130)
Rthe road speed
Accelerator pedal position
Your style of driving influences how the auto-
matic transmission shifts gear:
Rlittle throttle: early upshifts
Rmore throttle: late upshifts
130Automatic transmission
Driving an d parking
Problems with the transmission
ProblemPossible causes/consequences andMSolutions
The transmission has
problems shifting gear.The transmission is losing oil.
XHave the transmission checked at a qualified specialist workshop
immediately.
The acceleration ability
is deteriorating.
The transmission no lon-
ger changes gear.The transmission is in emergency mode.
It is only possible to shift intosecondgear and reverse gear.
XStop the vehicle.
XShift the transmission to position P.
XSwitch off the engine.
XWait at least ten seconds before restarting the engine.
XShift the transmission to positionDor R.
If D is selected, the transmission shifts into secondgear; ifRis
selected, the transmission shifts into reverse gear.
XHave the transmission checked at a qualified specialist workshop
immediately.
Transfer case
This section is only valid for vehicles with 4-
wheel drive (4MATIC). Power is always trans-
mitted to both axles.
!Performance tests may only be carried out
on a 2-axle dynamometer. The brake system
or transfer case could otherwise be damaged. Contact a qualified specialist workshop for a
performance test.
!If the parking brake is being tested on a
brake dynamometer, the ignition must be
switched off (SmartKey or Start/Stop button
in position 0or 1), as ESP
®will otherwise
automatically intervene. The brake system
could otherwise be damaged.
!Vehicles with 4MATIC must not be towed
with either the front or the rear axle raised, as
doing so will damage the transmission.
Refueling
Important safety notes
GWARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and explo-
sion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the auxiliary heating before refueling.
GWARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make sure that fuel does not come into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children.
If you or others come into contact with fuel,
observe the following:
RWash away fuel from skin immediately
using soap and water.
RIf fuel comes into contact with your eyes,
immediately rinse them thoroughly with
clean water. Seek medical assistance with-
out delay.
RIf fuel is swallowed, seek medical assis-
tance without delay. Do not induce vomit-
ing.
RImmediately change out of clothing which
has come into contact with fuel.
Refueling135
Driving and parking
Z
GWARNING
Electrostatic buildup can create sparks and
ignite fuel vapors. There is a risk of fire and
explosion.
Always touch the vehicle body before opening
the fuel filler flap or touching the fuel pump
nozzle. Any existing electrostatic buildup is
thereby discharged.
!Do not use diesel to refuel vehicles with a
gasoline engine. Do not switch on the ignition
if you accidentally refuel with the wrong fuel.
Otherwise, the fuel will enter the fuel system. Even small amounts of the wrong fuel could
result in damage to the fuel system and the
engine. Notify a qualified specialist workshop
and have the fuel tank and fuel lines drained
completely.
!Overfilling the fuel tank could damage the
fuel system.
!Take care not to spill any fuel on painted
surfaces. You could otherwise damage the
paintwork.
!Use a filter when refueling from a fuel can.
Otherwise, the fuel lines and/or injection sys-
tem could be blocked by particles from the
fuel can.
Do not get into the vehicle again during the refu-
eling process. Otherwise, electrostatic charge
could build up again.
If you overfill the fuel tank, fuel could spray out
when the fuel pump nozzle is removed.
iFlexible Fuel vehicles can be recognized by
the Ethanol up to E85 sticker on the inside of
the fuel filler flap.
For further information on fuel and fuel quality
(
Ypage 309).
Refueling
General information
Pay attention to the important safety notes
(Ypage 135).
The fuel filler flap is unlocked or locked auto-
matically when you unlock or lock the vehicle
with the key or using KEYLESS-GO. The position of the fuel filler cap is displayed
8
in the instrument cluster. The arrow next
to the filling pump indicates the side of the vehi-
cle.
Opening the fuel filler flap
:To open the fuel filler flap
;To insert the fuel filler cap
=Tire pressure table
?Instruction label for fuel type to be refueled
XSwitch off the engine.
XRemove the SmartKey from the ignition lock.
or, on vehicles with KEYLESS‑GO:
XOpen the driver's door.
The on-board electronics now have status 0.
This is the same as the SmartKey having been
removed.
XRemove the Start/Stop button from the igni-
tion lock (Ypage 122).
XPress the fuel filler flap in the direction of
arrow :.
The fuel filler flap opens slightly.
XOpen the fuel filler flap fully.
XTurn the fuel filler cap counterclockwise and
remove it.
XInsert the fuel filler cap into the holder
bracket on the inside of filler flap ;.
XCompletely insert the filler neck of the fuel
pump nozzle into the tank, hook in place and
refuel.
XOnly fill the tank until the pump nozzle
switches off.
Do not add any more fuel after the pump stops
filling for the first time. Otherwise, fuel may leak
out.
136Refueling
Driving and parking
To ensure that the vehicle is secured against
rolling away unintentionally:
Rthe parking brake must be applied.
Rthe transmission must be in positionPand the
Smartkey must be removed from the ignition lock.
Rthe front wheels must be turned towards the
curb on steep uphill or downhill gradients.
Switching off the engine
Important safety notes
GWARNING
The automatic transmission switches to neu-
tral position Nwhen you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
After switching off the engine, always switch
to parking position P. Prevent the parked vehi-
cle from rolling away by applying the parking
brake.
Vehicles with automatic transmission
XApply the parking brake firmly.
XShift the transmission to position P.
XWith the Smartkey:turn the Smartkey to
position 0in the ignition lock and remove it.
The immobilizer is activated.
XWith KEYLESS-GO: press the KEYLESS-GO
Start/Stop button (Ypage 122).
The engine stops and all the indicator lamps in
the instrument cluster go out.
When the driver's door is closed, this corre-
sponds to Smartkey position 1. When the
driver's door is open, this corresponds to
Smartkey position 0: "Smartkey removed".
If you switch the engine off with the transmis-
sion in position Ror D, the automatic transmis-
sion shifts to Nautomatically.
With the Smartkey: if you then open the driv-
er's door or the front-passenger door or remove the Smartkey from the ignition, the automatic
transmission shifts to Pautomatically.
With KEYLESS-GO: if you then open the driver's
or front-passenger door, the automatic trans-
mission shifts to P. If you want the automatic transmission to
remain in neutral
N, e.g. when having the vehicle
cleaned in an automatic car wash with a towing
system:
XVehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock.
XInsert the Smartkey into the ignition lock.
XAll vehicles: switch the ignition on.
XDepress the brake pedal and keep it
depressed.
XShift to neutral N.
XRelease the brake pedal.
XRelease the parking brake.
XSwitch off the ignition and leave the Smartkey
in the ignition lock.
Parking brake
GWARNING
If you must brake the vehicle with the parking brake, the braking distance is considerably
longer and the wheels could lock. There is an
increased danger of skidding and accidents.
Only use the parking brake to brake the vehi-
cle when the service brake is faulty. Do not
apply the parking brake too firmly. If the
wheels lock, release the parking brake until
the wheels begin turning again.
GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking position P.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. There is a risk of
an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children unsupervised in the vehicle.
Parking139
Driving and parking
Z
You have to depress the brake pedal more
firmly. Maintain a greater distance from the
vehicle in front.
After driving on a wet road or having the vehicle
washed, brake firmly while paying attention to
the traffic conditions. This will warm up the
brake discs, thereby drying them more quickly
and protecting them against corrosion.
Limited braking performance on salt-
treated roads
If you drive on salted roads, a layer of salt resi-
due may form on the brake discs and brake
pads. This can result in a significantly longer
braking distance.
RIn order to prevent any salt build-up, apply the
brakes occasionally while paying attention to
the traffic conditions.
RCarefully depress the brake pedal and the
beginning and end of a journey.
RMaintain a greater distance to the vehicle
ahead.
Servicing the brakes
!The brake fluid level may be too low, if:
Rif the red brake warning lamp lights up in
the instrument cluster and
Ryou hear a warning tone while the engine is
running
Observe additional warning messages in the
multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked immediately.
Consult a qualified specialist workshop to
arrange this.
!Vehicles with 4MATIC: function or per-
formance tests may only be carried out on a 2-
axle dynamometer. If you wish to operate the
vehicle on such a dynamometer, please con-
sult a qualified specialist workshop in
advance. You could otherwise damage the
drive train or the brake system.
!Vehicles with 4MATIC: as the ESP®sys-
tem operates automatically, the engine and
the ignition must be switched off (SmartKey in
position 0or 1in the ignition lock or Start/
Stop button in position 0or 1) while the park- ing brake is being tested on a brake dyna-
mometer.
Braking maneuvers triggered automatically
by ESP
®may seriously damage the brake sys-
tem.
!Vehicles with 4MATIC: as the ESP®sys-
tem operates automatically, the engine and
the ignition system must be switched off
(SmartKey in position 0or 1in the ignition
lock or Start/Stop button in position 0or 1)
when:
Rtesting the parking brake on a brake dyna-
mometer.
Ryou intend to have the vehicle towed with
the front axle raised.
Braking maneuvers triggered automatically
by ESP
®may seriously damage the brake sys-
tem.
All checks and maintenance work on the brake
system must be carried out at a qualified spe-
c
ialist workshop.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
If the brake system has only been subject to
moderate loads, you should test the functional-
ity of your brakes at regular intervals. To do so,
press firmly on the brake pedal when driving at a
high speed. This improves the grip of the brake
pads.
You can find a description of Brake Assist (BAS) on (
Ypage 63) or of BAS PLUS with Cross-Traffic
Assist on (Ypage 63).
The braking characteristics of the vehicle can be
seriously impaired if:
Rbrake pads other than those recommended
are installed
Rthe recommended brake fluid is not used
Safe braking can no longer be guaranteed.
Driving on wet roads
Hydroplaning
If water has accumulated to a certain depth on
the road surface, there is a danger of hydro-
planing occurring, even if:
Ryou drive at low speeds.
Rthe tires have adequate tread depth.
Driving tips143
Driving and parking
Z
iNote that Active Parking Assist cannot
measure the length of a parking space if it is at
right angles to the direction of travel. You will
need to judge whether your vehicle will fit into
the parking space.
When driving at speeds below 19 mph
(30 km/h), you will see the parking symbol as a
status indicator in the instrument cluster. When
a parking space has been detected, an arrow
towards the right or the left also appears. By
default, Active Parking Assist only displays park-
ing spaces on the front-passenger side. Parking spaces on the driver's side are displayed as
soon as the turn signal on the driver's side is
activated. When parking on the driver's side,
this must remain switched on until you acknowl-
edge the use of Active Parking Assist by press-
ing the abutton on the multifunction steer-
ing wheel. The system automatically determines
whether the parking space is parallel or at right
angles to the direction of travel.
A parking space is displayed while you are driv- ing past it, and until you are approximately 50 ft
(15 m) away from it.
Parking
GWARNING
If you leave the vehicle when it is only being
braked by Active Parking Assist it could roll
away if:
Rthere is a malfunction in the system or in
the voltage supply.
Rthe electrical system in the engine com-
partment, the battery or the fuses have
been tampered with.
Rthe battery is disconnected.
Rthe accelerator pedal has been depressed,
e.g. by a vehicle occupant.
There is a risk of an accident.
Before leaving the vehicle, always secure it
against rolling away.
iVehicles with automatic transmission:
When PARKTRONIC detects obstacles, Active
Parking Assist brakes automatically during
the parking process. You are responsible for
braking in good time.
XStop the vehicle when the parking space sym-
bol shows the desired parking space in the
instrument cluster.
XShift the transmission to position R.
The Start Park Assist? Yes: OK No:
% message appears in the multifunction
display.
XTo cancel the procedure: press the%
button on the multifunction steering wheel or pull away.
or
XTo park using Active Parking Assist: press
the a button on the multifunction steering
wheel.
The Park Assist Active Accelerate
and Brake Observe Surroundingsmes-
sage appears in the multifunction display.
XLet go of the multifunction steering wheel.
XBack up the vehicle, being ready to brake at all
times. When backing up, drive at a speed
below approximately 6 mph (10 km/h). Oth-
erwise Active Parking Assist will be canceled.
Active Parking Assist brakes the vehicle to a
standstill when the vehicle approaches the
rear border of the parking space.
Maneuvering may be required in tight parking
spaces.
The Park Assist Active Select D
Observe Surroundingsmessage appears in
the multifunction display.
XShift the transmission to position Dwhile the
vehicle is stationary.
Active Parking Assist immediately steers in
the other direction.
The Park Assist Active Accelerate
and Brake Observe Surroundingsmes-
sage appears in the multifunction display.
iYou will achieve the best results by waiting
for the steering procedure to complete before
pulling away.
XDrive forwards and be ready to brake at all
times.
Active Parking Assist brakes the vehicle to a
standstill.
The Park Assist Active Select R
Observe Surroundingsmessage appears in
the multifunction display.
Further transmission shifts may be necessary.
As soon as the parking procedure is complete,
the Park Assist Disabled
message appears
in the multifunction display and you will hear a
Driving systems163
Driving and parking
Z