
Problem
Possible causes/consequences and
0050
0050Solutions There is interference from a powerful source of radio waves.
X Unlock (Y page 81) or lock (Y page 81) the vehicle using the
mechanical key. KEYLESS-GO is malfunctioning.
X Lock/unlock the vehicle using the remote control function of the
SmartKey.
X Have the vehicle and SmartKey checked at a qualified specialist
workshop.
If the vehicle can also not be locked/unlocked using the remote con-
trol function:
X Unlock (Y page 81) or lock (Y page 81) the vehicle using the
mechanical key.
X Have the vehicle and SmartKey checked at a qualified specialist
workshop. The engine cannot be
started using the Smart-
Key. The on-board voltage is too low.
X Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary (Y page 317).
or X Jump-start the vehicle (Y page 318).
or X Consult a qualified specialist workshop. The engine cannot be
started using the Start/
Stop button. The Smart-
Key is in the vehicle. The vehicle is locked.
X Unlock the vehicle and try to start the vehicle again. The SmartKey battery is discharged or nearly discharged.
X Check the SmartKey battery (Y page 77) and replace it if necessary
(Y page 77).
If this does not work: X Start your vehicle with the SmartKey in the ignition lock. There is interference from a powerful source of radio waves.
X Start your vehicle with the SmartKey in the ignition lock. You have lost a Smart-
Key. X
Have the SmartKey deactivated at a qualified specialist workshop.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. You have lost the
mechanical key. X
Report the loss immediately to the vehicle insurers.
X If necessary, have the locks changed as well. SmartKey
79Opening and closing Z

Problems with the windshield wipers
Problem
Possible causes/consequences and
0050
0050Solutions The windshield wipers
are jammed. Leaves or snow, for example, may be obstructing the windshield wiper
movement. The wiper motor has been deactivated.
X For safety reasons, you should remove the SmartKey from the igni-
tion lock.
or X Switch off the engine using the Start/Stop button and open the
driver's door.
X Remove the cause of the obstruction.
X Switch the windshield wipers back on. The windshield wipers
fail completely. The windshield wiper drive is malfunctioning.
X Select another wiper speed on the combination switch.
X Have the windshield wipers checked at a qualified specialist work-
shop. 114
Windshield wipersLights and windshield wipers

Problems with the engine
Problem
Possible causes/consequences and
0050
0050Solutions The engine does not
start. The starter motor
can be heard. R
There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.
Before attempting to start the engine again:
X Turn the SmartKey in the ignition lock back to position 0092.
or X Press the Start/Stop button repeatedly until all indicator lamps in
the instrument cluster go out.
X Try to start the engine again (Y page 128). 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:
X Consult 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.
X Jump-start the vehicle (Y page 318).
If the engine does not start despite attempts to jump-start it:
X Consult a qualified specialist workshop. The starter motor was exposed to a thermal load that was too high.
X Allow the starter motor to cool down for approximately two minutes.
X Try to start the engine again.
If the engine still does not start: X Consult a qualified specialist workshop. Vehicles with a gasoline
engine:
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.
X Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic converter
and damage it.
X Have the cause rectified immediately at a qualified specialist work-
shop. The coolant temperature
gage 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.
X Stop as soon as possible and allow the engine and the coolant to
cool down.
X Check the coolant level (Y page 299). Observe the warning notes
as you do so and add coolant if necessary. Driving
133Driving and parking Z

Opening the fuel filler flap
0043
To open the fuel filler flap
0044 To insert the fuel filler cap
0087 Tire pressure table
0085 Instruction label for fuel type to be refueled
X Switch off the engine.
X Remove the SmartKey from the ignition lock.
or, in vehicles with KEYLESS-GO start-function
or KEYLESS‑GO
X Open the driver's door.
The vehicle electronics will now be in key
position 0092. This is the same as the SmartKey
having been removed.
The driver’s door can be closed again.
X Make sure that the engine cannot be started
via your smartphone (Y page 129).X
Press the fuel filler flap in the direction of
arrow 0043.
The fuel filler flap swings up.
X Turn the fuel filler cap counter-clockwise and
remove it.
X Insert the fuel filler cap into the holder
bracket on the inside of filler flap 0044.
X Completely insert the filler neck of the fuel
pump nozzle into the tank, hook in place and
refuel.
X Only 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 X
Replace the cap on the filler neck and turn
clockwise until it engages audibly.
X Close the fuel filler flap.
Close the fuel filler flap before locking the vehi-
cle.
If you are driving with the fuel filler cap open, the 00B6 reserve fuel warning lamp flashes. A mes-
sage appears in the multifunction display
(Y page 238).
In addition, the 00B9Check Engine warning
lamp may light up (Y page 259). Problems with fuel and the fuel tank
Problem
Possible causes/consequences and
0050 0050Solutions Fuel is leaking from the
vehicle.
G
WARNING
The fuel line or the fuel tank is faulty.
Risk of explosion or fire. X Apply the electric parking brake.
X Switch off the engine.
X Remove the SmartKey from the ignition lock.
or, in vehicles with KEYLESS-GO start-function or KEYLESS ‑GO
X Open the driver's door.
The vehicle electronics will now be in key position 0092. This is the
same as the SmartKey having been removed.
X Do not restart the engine under any circumstances.
X Consult a qualified specialist workshop. The fuel filler flap cannot
be opened. The fuel filler flap is not unlocked.
X Unlock the vehicle (Y page 74). Refueling
143Driving and parking Z

Wet roads
If you have driven for a long time in heavy rain
without braking, there may be a delayed reac-
tion from the brakes when braking for the first
time. This may also occur after the vehicle has
been washed or driven through deep water.
You then 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.
R Brake occasionally to remove any possible
salt residue. Make sure that you do not
endanger other road users when doing so.
R Carefully depress the brake pedal and the
beginning and end of a journey.
R Maintain a greater distance to the vehicle
ahead.
Servicing the brakes !
The brake fluid level may be too low, if:
R if the red brake warning lamp lights up in
the instrument cluster and
R you 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.
! A function or performance test should only
be carried out on a 2-axle dynamometer. If
you wish to operate the vehicle on such a
dynamometer, please consult a qualified spe-
cialist workshop in advance. You could oth-
erwise damage the drive train or the brake
system. !
Because ESP ®
is an automatic system, the
engine and ignition must be switched off
(SmartKey in position 0or 1or Start/Stop
button in position 0or 1) when the electric
parking brake is being tested on a brake dyna-
mometer (maximum 10 seconds).
Braking triggered automatically by ESP ®
may
seriously damage the brake system.
All checks and maintenance work on the brake
system must be carried out at a qualified spe-
cialist 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,
depress the brake pedal firmly when driving at a high speed. This improves the grip of the brake
pads.
You can find a description of Brake Assist (BAS)
on (Y page 65) or of BAS PLUS on (Y page 70).
Mercedes-Benz recommends that you only have brake pads/linings installed on your vehicle
which have been approved for Mercedes-Benz
vehicles or which correspond to an equivalent
quality standard. Brake pads/linings which have
not been approved for Mercedes-Benz vehicles
or which are not of an equivalent quality could
affect your vehicle's operating safety.
Mercedes-Benz recommends that you only use
brake fluid that has been specially approved for your vehicle by Mercedes-Benz, or which corre-
sponds to an equivalent quality standard. Brake fluid which has not been approved for
Mercedes-Benz vehicles or which is not of an
equivalent quality could affect your vehicle's
operating safety. 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:
R you drive at low speeds
R the tires have adequate tread depth 150
Driving tipsDriving and parking

vehicle rectified immediately at a qualified spe-
cialist workshop.
Do not shift into transmission position 005Cwhen
driving off-road. You could lose control of the
vehicle if you attempt to brake the vehicle using
the service brake. If the gradient is too steep for
your vehicle, drive back down in reverse gear.
General notes H
Environmental note
Protection of the environment is of primary
importance. Treat nature with respect.
Observe all prohibiting signs.
Read this section carefully before driving your
vehicle off-road. Practice by driving over more
gentle off-road terrain first.
Familiarize yourself with the characteristics of
your vehicle and the gear shift operation before
driving through difficult terrain.
The following driving systems are specially
adapted to off-road driving:
R AIRMATIC package (vehicle level)
(Y page 168)
R DSR (Downhill Speed Regulation)
(Y page 167)
Observe the following notes:
R Select a vehicle level that is suitable for the
terrain. To avoid damaging the vehicle, make
sure there is always sufficient ground clear-
ance.
R Check that items of luggage and loads are
stowed safely and are well secured
(Y page 276).
R Always keep the engine running and in gear
when driving on a downhill gradient. Activate
DSR (Y page 167).
R Always keep the engine running and in gear
when driving down an incline.
R Adapt your speed to the terrain. The rougher,
steeper or more ruts on the terrain, the slower
your speed should be.
R Do not jump with the vehicle as this will inter-
rupt the vehicle's propulsion.
R Drive with extreme care on unfamiliar off-road
routes where visibility is poor. For safety rea- sons, get out of the vehicle first and survey
the off-road route.
R Look out for obstacles, such as rocks, holes,
tree stumps and furrows. R
Take care when turning on an uphill or down-
hill slope or when driving across a slope. The
vehicle could otherwise tip over.
R Always keep the doors, the tailgate, the side
windows and the sliding sunroof closed while
the vehicle is in motion.
R Do not shift the automatic transmission to
position 005C.
R Observe the notes on off-road fording
(Y page 151).
i Information about retrofitting special all-ter-
rain tires is available from any qualified spe-
cialist workshop.
i Do not use the HOLD function when driving
off-road, on steep uphill or downhill gradients
or on slippery or loose surfaces. The HOLD
function cannot hold the vehicle on such sur- faces.
Checklist before driving off-road !
If the engine oil warning lamp lights up while
the vehicle is in motion, stop the vehicle in a
safe place as soon as possible. Check the
engine oil level. The engine oil warning lamp
warning must not be ignored. Continuing the
journey while the symbol is displayed could
lead to engine damage.
X Engine oil level: check the engine oil level
and add engine oil if necessary.
When you drive on steep gradients, the engine
oil level must be sufficiently high to ensure
that oil is supplied correctly in the vehicle.
X Tire-changing tool kit: check that the jack is
working and make sure you have the lug
wrench, a robust tow cable and a folding
spade in the vehicle.
X Wheels and tires: check the tread depth and
pressure of the tires.
X Check for damage and remove any foreign
objects, e.g. small stones, from the wheels/
tires.
X Replace any missing valve caps.
X Replace dented or damaged wheels.
X Rims: 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. Driving tips
153Driving and parking Z

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.
Driving over rough terrain 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.
X Deactivate DSR (Y page 167).
X Lower the vehicle level again to a level suita-
ble to the road conditions, e.g. to the normal
level.
X Clean the headlamps and rear lights and
check for damage.
X Clean the front and rear license plates.
X Clean the wheels and tires with a water jet
and remove any foreign objects.
X Clean the wheels, wheel housings and the
vehicle underside with a water jet; check for
any foreign objects and damage.
X Check 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 bellows of the axle joints
and propeller shafts.
X After the trip, examine without fail the entire
undercarriage, wheels, tires, brakes, body-
work structure, steering, chassis and exhaust system for damage.
X After driving for extended periods across
sand, mud, gravel, water or in similarly dirty
conditions, have the brake discs, wheels,
brake pads/linings and axle joints checked
and cleaned.
X If 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 on sand Observe the following rules when driving on
sand:
R Select a higher vehicle level.
R Avoid high engine speeds. R
Use the left-hand steering wheel paddle
shifter to shift to a lower gear appropriate to
the terrain.
R Drive quickly to overcome the rolling resist-
ance. Otherwise the vehicle's wheels could
become stuck in loose ground.
R Drive in the tracks of other vehicles if possi-
ble. Make sure that:
- the tire ruts are not too deep
- the sand is sufficiently firm
- the ground clearance of the vehicle is suf-
ficient.
Tire ruts and gravel roads !
Check that the ruts are not too deep and
that your vehicle has sufficient clearance.
Otherwise, your vehicle could be damaged or bottom out and get stuck.
Observe the following rules when driving along
ruts in off-road terrain or on roads with loose
gravel: R Select a higher vehicle level.
R Avoid high engine speeds.
R Shift to a lower gear using the left-hand steer-
ing wheel paddle shifter.
R Drive slowly.
R Where ruts are too deep, drive with the
wheels of one side on the center grassy area, if possible.
Driving over obstacles !
Obstacles could damage the floor of the
vehicle or components of the chassis. Ask
passengers for guidance when driving over
large obstacles. The passenger should always
keep a safe distance from the vehicle when
doing so in order to avoid injury as a result of unexpected vehicle movements. After driving
off-road or over obstacles, check the vehicle
for possible damage, especially to the under- body and the components of the chassis. 154
Driving tipsDriving and parking

Observe the following rules when driving over
tree stumps, large stones and other obstacles:
R Raise the vehicle level.
R Avoid high engine speeds.
R Shift to a lower gear using the left-hand steer-
ing wheel paddle shifter.
R Drive very slowly.
R Drive straight over the center of obstacles. Traveling uphill
Approach/departure angle G
WARNING
If you drive on a steep incline at an angle or
turn when driving on an incline, the vehicle
could slip sideways, tip and rollover. There is a risk of an accident.
Always drive on a steep incline in the line of
fall (straight up or down) and do not turn the
vehicle.
R Observe the rules on off-road driving.
R Do not drive at an angle on slopes, inclines or
gradients, but instead follow the direct line of
fall.
R When driving down an incline, make use of the
engine's braking effect. Observe the engine
speed; do not overrev the engine.
R Drive slowly.
R Avoid high engine speeds. Drive at appropri-
ate engine speeds (maximum 3,000 rpm).
R Use the left-hand steering wheel paddle
shifter to shift into a lower gear in good time
on long and steep downhill gradients.
R Check the brakes after prolonged off-road
driving. Hill start assist will aid you when pulling away on
a hill. For further information about hill start
assist, see (Y page 130).
Do not shift into transmission position 005Cwhen
driving off-road. You could lose control of the
vehicle if you attempt to brake the vehicle using
the service brake. If the gradient is too steep for
your vehicle, drive back down in reverse gear.
Always observe the approach/departure angle
values (Y page 366).
Maximum gradient-climbing capability Always observe the maximum gradient climbing
ability values (Y page 367).
Hilltops When driving up an uphill gradient, slightly
reduce pressure on the accelerator immediately
before reaching the brow of the hill. Make use of the vehicle's own impetus to travel over the
brow.
This style of driving prevents:
R the vehicle from lifting off the ground on the
brow of a hill
R the vehicle from traveling too quickly down
the other side
Driving downhill R
Drive slowly.
R Do not drive at an angle down steep inclines.
Steer into the line of fall and drive with the
front wheels aligned straight. Otherwise, the
vehicle could slip sideways, tip and rollover.
R Shift to a lower gear using the left-hand pad-
dle shifter before tackling steep downhill gra-
dients.
R Activate DSR. If this is not sufficient, brake
gently. When doing so, make sure that the
vehicle is facing in the direction of the line of
fall.
R Check that the brakes are working normally
after a long downhill stretch.
i The special off-road ABS setting enables a
precise, brief and repeated locking of the
front wheels. This causes them to dig into
loose earth. Be aware that the front wheels
easily skid across the ground surface if com-
pletely braked and therefore lose their ability
to steer. Driving tips
155Driving and parking Z