Problems with the engine
ProblemPossible causes/consequences andMSolutions
The engine does not
start.The HOLD function or DISTRONIC PLUS is activated.
XDeactivate the HOLD function (Ypage 193) or DISTRONIC
PLUS (
Ypage 186).
XTry to start the engine again.
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 151). 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 331).
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.
156Driving
Driving and parking
!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
system could be blocked by particles from
the fuel can.
Do not get into the vehicle again during the
refueling 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.
For further information on fuel and fuel quality (
Ypage 377).
Refueling
General information
The fuel filler flap is unlocked/locked auto-
matically when you unlock/lock the vehicle
with the SmartKey.
The position of the fuel filler cap is displayed
æ in the instrument cluster. The arrow on
the filling pump indicates the side of the vehi-
cle.
Opening the fuel filler flap
:To open the fuel filler flap
;Tire pressure table
=To insert the fuel filler cap
?Instruction label for fuel type to be refu-
eled
XVehicles without KEYLESS-GO: remove
the SmartKey from the ignition lock.
XVehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: open the driver's
door.
The on-board electronics now have status
0. This is the same as the SmartKey having
been removed.
XPress the fuel filler flap in the direction of
arrow :.
The fuel filler flap swings up.
XTurn the fuel filler cap counterclockwise
and remove it.
XInsert the fuel filler cap into the holder on
the inside of fuel 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.
Closing the fuel filler flap
XReplace the cap on the filler neck and turn
clockwise until it engages audibly.
XClose the fuel filler flap.
Close the fuel filler flap before locking the
vehicle.
If you are driving with the fuel filler cap open,
the 8 reserve fuel warning lamp flashes. A
message appears in the multifunction display
(
Ypage 252).
In addition, the ;Check Engine warning
lamp may light up (
Ypage 275).
For further information on warning and indi-
cator lamps in the instrument cluster, see
(
Ypage 275).
170Refueling
Driving and parking
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 electric parking brake.
XAll vehicles (except Mercedes-AMG
vehicles): shift the transmission to posi-
tion P.
XMercedes-AMG vehicles: press but-
ton :.
XWith the SmartKey: turn the SmartKey to
position 0in the ignition lock and remove it.
The immobilizer is activated.
XWith the Start/Stop button: press the
Start/Stop button (
Ypage 149).
The engine stops and all the indicator
lamps in the instrument cluster go out.
When the driver's door is closed, this cor-
responds 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 trans-
mission in position
Ror D, the automatic
transmission shifts to Nautomatically.
With the SmartKey: if you then open the
driver's door or the front-passenger door or
remove the SmartKey from the ignition, the
automatic transmission shifts to Pautomati-
cally.
With the Start/Stop button: if you then
open the driver's door or the front-passenger door, the automatic transmission shifts to P
automatically.
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:
Using the SmartKey:
XSwitch on the ignition.
XDepress the brake pedal and keep it
depressed.
XShift to neutral N.
XRelease the brake pedal.
XRelease the electric parking brake.
XSwitch off the ignition and leave the Smart-
Key in the ignition lock.
With the Start/Stop button:
XRemove the Start/Stop button from the
ignition lock.
XInsert the SmartKey into the ignition lock.
XSwitch on the ignition.
XDepress the brake pedal and keep it
depressed.
XShift to neutral N.
XRelease the brake pedal.
XRelease the electric parking brake.
XSwitch off the ignition and leave the Smart-
Key in the ignition lock.
If you attempt to turn off the engine when the
selector lever is not in position P:
Ra message appears in the multifunction dis-
play
Ra warning signal sounds
172Parking
Driving and parking
function cannot hold the vehicle on such sur-
faces.
Checklist before driving off-road
XEngine oil level:check the engine oil level
and add oil if necessary.
When driving on steep gradients, the
engine oil level must be sufficiently high to
ensure a correct oil supply in the vehicle.
XWheels and tires: check the tire tread
depth and tire pressure.
XCheck for damage and remove any foreign
objects, e.g. small stones, from the
wheels/tires.
XReplace any missing valve caps.
XReplace dented or damaged wheels.
XRims: dented or bent rims can result in a
loss of tire pressure and damage the tire
bead. Before driving off-road, check the
wheels and replace them if necessary.
Checklist after driving off-road
!If you detect damage to the vehicle after
driving off-road, have the vehicle checked
immediately at a qualified specialist work-
shop.
XDeactivate off-road program (Ypage 157).
XDeactivate DSR (Ypage 197).
XClean the headlamps and rear lights and
check for damage.
XClean the front and rear license plates.
XClean the wheels and tires with a water jet and remove any foreign objects.
XClean the wheels, wheel housings and the
vehicle underside with a water jet; check
for any foreign objects and damage.
XCheck whether twigs or other parts of
plants have become trapped. These
increase the risk of fire and can damage
fuel pipes, brake hoses or the rubber bel-
lows of the axle joints and propeller shafts.
XAfter the trip, examine without fail the
entire undercarriage, wheels, tires, brakes, bodywork structure, steering, chassis and
exhaust system for damage.
XAfter driving in sand, mud, gravel, water or
similar dirty conditions, have the following
checked and cleaned:
Rbrake discs
Rwheels
Rbrake pads
Raxle joints
XIf you detect strong vibrations after off-road
travel, check for foreign objects in the
wheels and drive train and remove them if
necessary. Foreign objects can disturb the
balance and cause vibrations.
Driving over poor road surfaces places
greater demands on your vehicle than driving
on normal roads. After driving off-road, check
the vehicle. This allows you to detect damage promptly and reduce the risk of an accident to
yourself and other road users.
Driving on sand
Observe the following rules when driving on
sand:
RActivate the off-road program
(
Ypage 157).
RAvoid high engine speeds.
RUse the left-hand steering wheel paddle
shifter to shift to a lower gear appropriate
to the terrain.
RDrive quickly to overcome the rolling resist-ance. Otherwise the vehicle's wheels could
become stuck in loose ground.
RDrive in the tracks of other vehicles if pos-
sible. Make sure that:
-the tire ruts are not too deep.
-the sand is sufficiently firm.
-the ground clearance of the vehicle is
sufficient.
Tire ruts and gravel roads
!Check that the ruts are not too deep and
that your vehicle has sufficient clearance.
182Driving tips
Driving and parking
Monitoring range of the sensors
In particular, the detection of obstacles can
be impaired if:
Rthere is dirt on the sensors or anything elsecovering the sensors
Rthere is poor visibility, e.g. due to fog, heavy
rain or snow
Ra narrow vehicle traveling in front, e.g. a
motorbike or bicycle
Rthe road has very wide lanes
Rthe road has narrow lanes
Ryou are not driving in the middle of the lane
Rthere are barriers or similar lane borders
Vehicles in the monitoring range are then not
indicated.
Blind Spot Assist monitors the area up to 10 ft
(3 m) behind your vehicle and directly next to
your vehicle, as shown in the diagram.
If the lanes are narrow, vehicles driving in the
lane beyond the lane next to your vehicle may
be indicated, especially if the vehicles are not
driving in the middle of their lane. This may be
the case if the vehicles are driving on the inner
side of their lane. Due to the nature of the system:
Rwarnings may be issued in error when driv-
ing close to crash barriers or similar solid
lane borders.
Rwarnings may be interrupted when driving
alongside particularly long vehicles, e.g.
trucks, for a prolonged time.
Warning display
:Warning display
Blind Spot Assist is not active at speeds below
approximately 20 mph (30 km/h). Vehicles in
the monitoring range are then not indicated.
When Blind Spot Assist is activated, indicator
lamp :in the exterior mirrors lights up yel-
low at speeds of up to 20 mph (30 km/h). At
speeds above 20 mph (30 km/h), the indica-
tor lamp goes out and Blind Spot Assist is
operational.
If a vehicle is detected within the blind spot
monitoring range at speeds above 20 mph
(30 km/h), warning lamp :on the corre-
sponding side lights up red. This warning is
always emitted when a vehicle enters the
blind spot monitoring range from behind or
from the side. When you overtake a vehicle,
the warning only occurs if the difference in
speed is less than 7 mph (12 km/h).
The yellow indicator lamp goes out if reverse
gear is engaged. In this event, Blind Spot
Assist is no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light.
214Driving systems
Driving and parking
Collision warning
If a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the
corresponding turn signal, a double warning
tone sounds. Red warning lamp :flashes. If
the turn signal remains on, vehicles detected
are indicated by the flashing of red warning
lamp :. There are no further warning tones.
Switching on Blind Spot Assist
XMake sure that Blind Spot Assist is activa-
ted in the on-board computer
(
Ypage 228).
XTurn the SmartKey to position 2in the igni-
tion lock.
Warning lamps :in the exterior mirrors
light up red for approximately 1.5 seconds
and then turn yellow.
Lane Keeping Assist
General notes
Lane Keeping Assist monitors the area in
front of your vehicle by means of multifunc-
tion camera :which is attached behind the
top of the windshield. Active Lane Keeping
Assist detects lane markings on the road and
can warn you before you leave your lane unin- tentionally.
This function is available in the range between
40 mph and 120 mph (60 km/h and
200 km/h).
A warning may be given if a front wheel
passes over a lane marking. It will warn you by
means of intermittent vibration in the steer-
ing wheel for up to 1.5 seconds. Important safety notes
GWARNING
Lane Keeping Assist may not always clearly
recognize lane markings.
In this case, Lane Keeping Assist may:
Rgive an unnecessary warning
Rnot give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and stay in lane, in particular if
warned by Lane Keeping Assist.
GWARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There is
a risk of an accident.
You should always steer, brake or accelerate
yourself, in particular if warned by Lane Keep-
ing Assist.
If you fail to adapt your driving style, Lane
Keeping Assist can neither reduce the risk of
an accident nor override the laws of physics.
Lane Keeping Assist cannot take into account
the road, traffic and weather conditions. Lane
Keeping Assist is merely an aid. You are
responsible for the distance to the vehicle in
front, for vehicle speed, for braking in good
time and for staying in your lane.
The Lane Keeping Assist does not keep the
vehicle in the lane.
The system may be impaired or may not func- tion if:
Rthere is poor visibility, e.g. due to insuffi-
cient illumination of the road, or due to
snow, rain, fog or spray
Rthere is glare, e.g. from oncoming traffic,
the sun or reflection from other vehicles
(e.g. if the road surface is wet)
Rthe windshield is dirty, fogged up, damagedor covered, for instance by a sticker, in the
vicinity of the camera
Rthere are no, several or unclear lane mark-
ings for a lane, e.g. in areas with road con-
struction work
Driving systems215
Driving and parking
Z
ProblemPossible causes/consequences andMSolutions
F(USA only)
! (Canada only)
The red indicator lamp
for the electric parking
brake flashes or lights
up and/or the yellow
warning lamp for the
electric parking brake
lights up.XObserve the additional display messages in the multifunction
display.
6
The red restraint sys-
tem warning lamp is lit
while the engine is run-
ning.The restraint system is faulty.
GWARNING
The air bags or Emergency Tensioning Devices may either be trig-
gered unintentionally or, in the event of an accident, may not be
triggered.
There is an increased risk of injury.
XObserve the additional display messages in the multifunction
display.
XDrive on carefully.
XContact a qualified specialist workshop and have the restraint
system checked.
For further information about the restraint system, see
(
Ypage 42).
274Warning and indicator lamps in the instrument cluster
On-board computer and displays
Do not start the vehicle using a rapid charging device. If your vehicle's battery is discharged,
the engine can be jump-started from another vehicle or from a second battery using jumper
cables. Observe the following points:
RThe battery is not accessible in all vehicles. If the other vehicle's battery is not accessible,
jump-start the vehicle using a second battery or a jump-starting device.
RYou may only jump-start the vehicle when the engine and exhaust system are cold.
RDo not start the engine if the battery is frozen. Let the battery thaw first.
ROnly jump-start from batteries with a 12 V voltage rating.
ROnly use jumper cables that are not damaged and have a sufficient cross-section and insu-
lated terminal clamps.
RMake sure that the two vehicles do not touch.
Make sure that:
Rthe jumper cables are not damaged.
Rnon-insulated parts of the terminal clamps do not come into contact with other metal parts
while the jumper cables are connected to the battery.
RThe jumper cables cannot come into contact with parts which can move when the engine is
running, such as the V-belt pulley or the fan.
XSecure the vehicle by applying the electric parking brake.
XShift the transmission to position P.
XTurn the SmartKey to position 0in the ignition lock and remove it.
XSwitch off all electrical consumers, e.g. rear window defroster, lighting, etc.
XOpen the hood.
Position number Bidentifies the charged battery of the other vehicle or an equivalent jump-
starting device.
XPress together cover :of positive clamp ;and slide it back.
XConnect positive terminal ;on your vehicle to positive terminal =of donor battery B
using the jumper cable, beginning with your own battery.
332Jump-starting
Breakdown assistance