
Display messagesPossible causes/consequences and M SolutionsDISTRONIC PLUS
Currently
Unavailable See
Oper. ManualDISTRONIC is deactivated and temporarily inoperative. Possible
causes are:
R the DISTRONIC PLUS cover in the radiator grill is dirty.
R function is impaired due to heavy rain or snow.
R the sensors in the bumpers are dirty.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
A warning tone also sounds.
If the display message does not disappear:XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XApply the electric parking brake.XClean the DISTRONIC PLUS cover in the radiator grill
( Y page 470).XClean the bumpers ( Y page 470).XRestart the engine.
If the system detects that the sensors are fully operational, the
display message disappears.
DISTRONIC is operational again.
DISTRONIC PLUS
InoperativeDISTRONIC PLUS is defective. BAS PLUS (Brake Assist PLUS) and
PRE-SAFE ®
Brake may be inoperative as well.
A warning tone also sounds.XVisit a qualified specialist workshop.DISTRONIC PLUS
OverrideYou have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.XTake your foot off the accelerator pedal.DISTRONIC PLUS
--- mphAn activation condition for DISTRONIC PLUS is not fulfilled.XCheck the activation conditions for DISTRONIC PLUS
( Y page 336).416Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsCheck
TiresGRisk of accident
The tire pressure in one or more tires has dropped significantly.
The wheel position is displayed in the multifunction display.
A warning tone also sounds.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XCorrect the tire pressure ( Y page 499).XIf necessary, change a wheel ( Y page 515).Caution
Tire DefectGRisk of accident
The tire pressure in one or more tires has dropped suddenly. The
wheel position is shown in the multifunction display.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XIf necessary, change a wheel ( Y page 515).Tire Pressure
Please RectifyThe tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great.XCheck the tire pressures at the next opportunity. If necessary,
correct the tire pressure ( Y page 499).XRestart the tire pressure monitor ( Y page 501).Wheel sensor(s)
MissingThere is no signal from the tire pressure sensor of one or several
wheels. The pressure of the affected tire is not displayed in the
multifunction display.XHave the faulty tire pressure sensor replaced at a qualified
specialist workshop.Tire Pressure
Monitor
Currently
UnavailableDue to a source of radio interference, no signals can be received
from the wheel sensors. The tire pressure monitor is temporarily
malfunctioning.XDrive on.
The tire pressure monitor restarts automatically as soon as the
problem has been solved.h
Tire Press.
Warning Caution
Tire MalfunctionGRisk of accident
The tire pressure in one or more tires has dropped suddenly.
A warning tone also sounds.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XIf necessary, change a wheel ( Y page 515).418Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M Solutionsh
Check Tire PressureGRisk of accident
The tire pressure in one or more tires has dropped significantly.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.XIf necessary, change a wheel ( Y page 515).XCheck the tire pressure. If necessary, correct the tire pressure
( Y page 499).h
Correct Tire
PressureThe tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great.XCheck the tire pressures at the next opportunity. If necessary,
correct the tire pressure ( Y page 499).
Vehicle
Display messagesPossible causes/consequences and M SolutionsShift to P or N
to Start EngineYou have attempted to start the engine with the transmission in
position R or D.XShift the transmission to position P or N.Auxiliary Battery
Malfunction
(White display
message)The auxiliary battery for the automatic transmission is no longer
being charged.XVisit a qualified specialist workshop.Auxiliary Battery
Malfunction
(Red display message)The auxiliary battery for the automatic transmission is discharged.
If there is a malfunction in the vehicle's electrical system, you may
not be able to change the transmission position.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.XConsult a qualified specialist workshop.Apply Brake to
Shift from 'P'You have attempted to move the transmission selector lever to
position D, R or N without depressing the brake pedal.XDepress the brake pedal.Door Open
Vehicle Not in ParkThe driver's door is open and the transmission is in position R, N
or D.XShift the transmission to position P.XApply the electric parking brake.Display messages419On-board computer and displaysZ

SmartKeyDisplay messagesPossible causes/consequences and M SolutionsÂ
Key Does Not
Belong to VehicleYou have put the wrong SmartKey in the ignition lock.XUse the correct SmartKey.Â
Take Your Key From
IgnitionThe SmartKey is in the ignition lock.XRemove the SmartKey.Â
Obtain a New KeyThe SmartKey needs to be replaced.XVisit a qualified specialist workshop.Â
Replace Key BatteryThe batteries of the KEYLESS-GO key are discharged.XChange the batteries ( Y page 85).Â
Don't Forget Your
KeyThe display message is shown for a maximum of 60 seconds and
is only a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.XRemember to take the KEYLESS-GO key with you when you
leave the vehicle.Â
Key Not
Detected (Red display
message)The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XApply the electric parking brake.XLocate the KEYLESS-GO key.The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
A warning tone also sounds.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XApply the electric parking brake.XOperate the vehicle with the SmartKey in the ignition lock.Display messages421On-board computer and displaysZ

consumption may be higher than this when
the vehicle is new or if you frequently drive at
high engine speeds.
On vehicles with a 12-cylinder engine, the oil
level can be checked using the on-board
computer. On all other models, the oil
dipstick must be used to check the engine oil
level.
Depending on the engine, the oil dipstick may
be in a different location.
When checking the oil level:
R park the vehicle on a level surface.
R the engine should be switched off for
approximately five minutes if the engine is
at normal operating temperature.
R if the engine is not at normal operating
temperature, e.g. if the engine was only
started briefly: wait about 30 minutes
before carrying out the measurement.Checking the oil level using the oil
dipstick
Example: vehicles with a gasoline engine
Example: vehicles with 4MATIC
XPull oil dipstick : out of the dipstick guide
tube.XWipe off oil dipstick :.XSlowly slide oil dipstick : into the guide
tube to the stop, and take it out again.
If the level is between MIN mark = and
MAX mark ;, the oil level is correct.XIf the oil level is at or below MIN mark =,
add 0.55 US qt to 1.1 US qt ( 0.5 to 1.0 l) of
engine oil.
Checking the oil level using the on-
board computer
Measurement
XMake sure that the SmartKey is in position
2 in the ignition lock.XPress the ; or = button to select the
Service menu.460Engine compartmentMaintenance and care

XPark the vehicle on a level surface.
Only check the coolant level when the
vehicle is on a level surface and the engine
has cooled down.XTurn the SmartKey to position 2 in the
ignition lock ( Y page 307).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice ( Y page 307).XCheck the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
158 ‡ (70 †).XTurn the SmartKey to position
0 (Y page 307) in the ignition lock.XSlowly turn cap : half a turn
counterclockwise to allow excess pressure
to escape.XTurn cap : further counterclockwise and
remove it.
If the coolant is at the level of marker bar
= in the filler neck when cold, there is
enough coolant in coolant expansion
tank ;.
If the coolant level is approximately 0.6 in
(1.5 cm) above marker bar = in the filler
neck when warm, there is enough coolant
in coolant expansion tank ;.XIf necessary, add coolant that has been
tested and approved by Mercedes-Benz.XReplace cap : and turn it clockwise as far
as it will go.
For further information on coolant, see
( Y page 530).
Adding washer fluid to the windshield
washer system/headlamp cleaning
systemGWARNING
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned.
Example: washer fluid reservoir
Depending on the engine, the washer fluid
reservoir may be installed in different
locations.
XTo open: pull cap : upwards by the tab.XAdd the premixed washer fluid.XTo close: press cap : onto the filler neck
until it engages.
The washer fluid reservoir is used for both the
windshield washer system and the headlamp
cleaning system.
Further information on windshield washer
fluid/antifreeze ( Y page 531).
Brake fluid level
! If the brake fluid level in the brake fluid
reservoir has fallen to the MIN mark or
below, check the brake system
immediately for leaks. Also check the
thickness of the brake linings. Visit a
qualified specialist workshop immediately.
Do not add brake fluid. This does not
correct the malfunction.
464Engine compartmentMaintenance and care

position P automatically and locks the
wheels. You can prevent this by shifting
the automatic transmission to N
beforehand.
R Vehicles with KEYLESS-GO:
Do not open the driver's door or front-
passenger door when the engine is
switched off. Otherwise, the automatic
transmission selects park position P
automatically and locks the wheels.
Observe the following to make sure that the
automatic transmission stays in position N:XMake sure the vehicle is stationary and the
ignition is switched off.XTurn the key to position 2(Y page 307) in
the ignition lock.
Use the SmartKey instead of the Start/
Stop button on vehicles with KEYLESS-GO.XDepress and hold the brake pedal.XShift the automatic transmission to
position N.XRelease the brake pedal.XRelease the electric parking brake.XSwitch off the ignition and leave the
SmartKey in the ignition lock.
! Make sure that:
R the side windows and the sliding sunroof
are fully closed.
R the ventilation/heating is switched off
(the OFF button has been pressed).
R the windshield wiper switch is in position
0 .
Otherwise, the vehicle might be damaged.
After using an automatic car wash, wipe off
wax from the windshield and the wiper
blades. This will prevent smears and reduce
wiping noises caused by residue on the
windshield.
Washing by hand
In some countries, washing by hand is only
allowed at specially equipped washing bays.
Observe the legal requirements in all
countries concerned.XDo not use hot water and do not wash the
vehicle in direct sunlight.XUse a soft sponge to clean.XUse a mild cleaning agent, such as a car
shampoo approved by Mercedes-Benz.XThoroughly hose down the vehicle with a
gentle jet of water.XDo not point the water jet directly towards
the air inlet.XUse plenty of water and rinse out the
sponge frequently.XRinse the vehicle with clean water and dry
thoroughly with a chamois.XDo not let the cleaning agent dry on the
paintwork.
When using the vehicle in winter, remove all
traces of road salt deposits carefully and as
soon as possible.
Power washers
GWARNING
Do not use power washers with circular-jet
nozzles (dirt grinders) to clean your vehicle, in
particular the tires. You could otherwise
damage the tires and cause an accident.
! Always maintain a distance of at least
11.8 in (30 cm) between the vehicle and the
power washer nozzle. Information about
the correct distance is available from the
equipment manufacturer.
Move the power washer nozzle around
when cleaning your vehicle.
Do not aim directly at any of the following:
R tires
R door gaps, roof gaps, joints, etc.
R electrical components
R battery
R connectors
R lights
R seals
Care467Maintenance and careZ

Always have paintwork repairs carried out
at a qualified specialist workshop.
! Do not use wash programs with a hot wax
treatment under any circumstances.
i The vehicle should preferably be washed
by hand using a soft sponge, car shampoo
and plenty of water.
i Use only insect remover and car shampoo
from the range of recommended and
approved Mercedes-Benz care products.
Cleaning the windowsGWARNING
Before cleaning the windshield or wiper
blades, switch off the windshield wipers and
remove the SmartKey from the ignition lock.
On vehicles with KEYLESS-GO, press the
Start/Stop button repeatedly until all
indicator lamps in the instrument cluster have
gone out. The windshield wipers could
otherwise move and injure you.
! Only fold the windshield wipers away from
the windshield when vertical. Otherwise,
you will damage the hood.
XClean the inside and outside of the
windows with a damp cloth and a cleaning
agent that is recommended and approved
by Mercedes-Benz.
! Do not use dry cloths, abrasive products,
solvents or cleaning agents containing
solvents to clean the inside of the windows.
Do not touch the insides of the windows
with hard objects, e.g. an ice scraper or
ring. There is otherwise a risk of damaging
the windows.
! Clean the water drainage channels of the
windshield and the rear window at regular
intervals. Deposits such as leaves, petals
and pollen may under certain
circumstances prevent water from draining
away. This can lead to corrosion damage
and damage to electronic components.
Cleaning the wiper bladesGWARNING
Before cleaning the windshield or wiper
blades, switch off the windshield wipers and
remove the SmartKey from the ignition lock.
On vehicles with KEYLESS-GO, press the
Start/Stop button repeatedly until all
indicator lamps in the instrument cluster have
gone out. The windshield wipers could
otherwise move and injure you.
! Only fold the windshield wipers away from
the windshield when vertical. Otherwise,
you will damage the hood.
! Do not pull the wiper blade. Otherwise,
the wiper blade could be damaged.
! Do not clean wiper blades too often and
do not rub them too hard. Otherwise, the
graphite coating could be damaged. This
could cause wiper noise.
XFold the wiper arms away from the
windshield.XCarefully clean the wiper blades with a
damp cloth.XFold the windshield wipers back again
before switching on the ignition.
! Hold the wiper arm securely when folding
back. The windshield could be damaged if
the wiper arm smacks against it suddenly.
Cleaning the exterior lighting
! Only use cleaning agents or cleaning
cloths which are suitable for plastic light
lenses. Unsuitable cleaning agents or
cleaning cloths could scratch or damage
the plastic light lenses.
XClean the plastic lenses of the exterior
lighting using a wet sponge and a mild
cleaning agent, e.g. Mercedes-Benz car
shampoo. Or clean the exterior lighting
with cleaning cloths.Care469Maintenance and careZ