Engine
Problem
Possible causes/consequences and
0050
0050Solutions 00B9
The yellow Check
Engine warning lamp
lights up while the
engine is running.
There may be a malfunction, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system (for vehicles with gasoline engines)
R in the fuel system
The emission limit values may be exceeded and the engine may be
in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states, you must immediately visit a qualified special-
ist workshop as soon as the yellow Check Engine warning lamp
lights up. This is due to the legal requirements in effect in these
states. If in doubt, check whether such legal regulations apply in the state in which you are currently driving. Vehicles with a diesel engine: the fuel tank has been run dry
(Y
page 188).
X Start the engine three to four times after refueling.
If the yellow Check Engine warning lamp goes out, emergency
running mode is canceled. The vehicle need not be checked. 00B6
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.
The fuel level has dropped into the reserve range.
X Refuel at the nearest gas station. 00B6
The yellow reserve fuel
warning lamp flashes
while the vehicle is in
motion.
In addition, the
00B9
Check Engine warning
lamp may light up. The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.
X Check that the fuel filler cap is correctly closed.
X If the fuel filler cap is not correctly closed: close the fuel filler
cap.
X If the fuel filler cap is closed: visit a qualified specialist work-
shop. Warning and indicator lamps in the instrument cluster
335On-board computer and displays Z
Problem
Possible causes/consequences and
0050
0050Solutions 00AC
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature gauge is at the start of the scale. The temperature sensor for the coolant temperature gage is defec-
tive.
The coolant temperature is no longer being monitored. There is a risk of engine damage if the coolant temperature is too high.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions. Do not continue
driving under any circumstances.
X Secure the vehicle against rolling away (Y page 190).
X Consult a qualified specialist workshop. 336
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Problem
Possible causes/consequences and
0050
0050Solutions 00AC
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
The coolant level is too low.
! Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
If the coolant level is correct, the airflow to the engine radiator may be blocked or the electric engine radiator fan may be malfunc-
tioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 190).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and add coolant, observing the warning
notes (Y page 375).
X If you need to add coolant more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the coolant temperature is
below 248 ‡(120 †). Otherwise, the engine could be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic. 00AC
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 248 ‡ (120 †). The air-
flow to the engine radiator may be blocked or the coolant level may
be too low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury. Warning and indicator lamps in the instrument cluster
337On-board computer and displays Z
Problem
Possible causes/consequences and
0050
0050Solutions X
Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 190).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and add coolant, observing the warning
notes (Y page 375).
X If you need to add coolant more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X At coolant temperatures below 248 ‡ (120 †), drive to the
nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-and-go traffic. Driving systems
Problem
Possible causes/consequences and
0050 0050Solutions 00BA
The red distance warn-
ing function warning
lamp comes on while
the vehicle is moving. A
warning tone also
sounds. You are approaching a vehicle or a stationary obstacle in your line
of travel at too high a speed.
X Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to
brake or take evasive action.
Further information on DISTRONIC PLUS (Y page 206).
Further information on PRE‑ SAFE®
Brake (Y page 76).
Further information on the distance warning function (Y page 70).338
Warning and indicator lamps in the instrument clusterOn-board computer and displays
Tires
Problem
Possible causes/consequences and
0050
0050Solutions 0077
The yellow tire pressure
monitor warning lamp
(pressure loss/
malfunction) is lit. The tire pressure monitor has detected a loss of pressure in at
least one of the tires.
G WARNING
With tire pressures which are too low, there is a risk of the fol-
lowing hazards:
R they may burst, especially as the load and vehicle speed
increase.
R they may wear excessively and/or unevenly, which may greatly
impair tire traction.
R the driving characteristics, as well as steering and braking, may
be greatly impaired.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away (Y page 190).
X Observe the additional display messages in the multifunction
display.
X Check the tires and, if necessary, follow the instructions for a
flat tire (Y page 389).
X Check the tire pressure (Y page 414).
X If necessary, correct the tire pressure. 0077
The yellow tire pressure
monitor warning lamp
(pressure loss/
malfunction) flashes for
approximately one
minute and then
remains lit. The tire pressure monitor is faulty.
G WARNING
The system is possibly unable to recognize or register low tire
pressure.
There is a risk of an accident.
X Observe the additional display messages in the multifunction
display.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
339On-board computer and displays Z
to the instrument cluster in the driver's
field of vision.
X Stop after driving for approximately ten
minutes and check the tire pressure with
the tire inflation compressor.
The tire pressure must now be at least
130 kPa (1.3 bar/19 psi). G
WARNING
If the required tire pressure is not reached
after driving for a short period, the tire is too
badly damaged. The tire sealant cannot repair the tire in this instance. Damaged tires and a
tire pressure that is too low can significantly
impair the vehicle's braking and driving char-
acteristics. There is a risk of accident.
Do not continue driving. Contact a qualified
specialist workshop.
i In cases such as the one mentioned
above, contact an authorized Mercedes-
Benz Center. Or call 1-800-FOR-MERCedes
(in the USA) or 1-800-387-0100 (in Can-
ada).
X Correct the tire pressure if it is still at least
130 kPa (1.3 ba r/19 psi). See the Tire and
Loading Information placard on the driver's side B-pillaro r the tire pressure table in the
fuel filler flap for values.
X To increase the tire pressure: switch on
the tire inflation compressor. 006D
Pressure release button
006E Pressure gauge
X To reduce the tire pressure: press pres-
sure release button 006Don the filler hose. X
Stow the tire sealant bottle and the tire
inflation compressor.
X Drive to the nearest qualified specialist
workshop and have the tire changed there.
X Have the tire sealant bottle replaced as
soon as possible at a qualified specialist
workshop.
X Have the tire sealant bottle replaced every
four years at a qualified specialist work-
shop. Battery (vehicle)
Important safety notes
Special tools and expert knowledge are
required when working on the battery, e.g.
removal and installing. You should therefore
have all work involving the battery carried out
at a qualified specialist workshop. G
WARNING
Work carried out incorrectly on the battery
can lead, for example, to a short circuit and
thus damage the vehicle electronics. This can lead to function restrictions applying to
safety-relevant systems, e.g. the lighting sys-
tem, ABS (anti-lock braking system) or ESP ®
(Electronic Stability Program). The operating
safety of your vehicle may be restricted. You
could lose control of the vehicle, for example:
R braking
R in the event of abrupt steering maneuver
and/or when the vehicle's speed is not
adapted to the road conditions
There is a risk of an accident.
In the event of a short circuit or a similar inci- dent, contact a qualified specialist workshop
immediately. Do not drive any further. You
should have all work involving the battery car-
ried out at a qualified specialist workshop.
i For further information about ABS and
ESP ®
, see (Y page 68) and (Y page 73). Battery (vehicle)
393Breakdown assistance Z
G
WARNING
Electrostatic build-up can lead to the creation of sparks, which could ignite the highly explo-
sive gases of a battery. There is a risk of an
explosion.
Before handling the battery, touch the vehicle body to remove any existing electrostatic
build-up.
The highly flammable gas mixture forms when
charging the battery as well as when jump-
starting.
Always make sure that neither you nor the
battery is electrostatically charged. A build-
up of electrostatic charge can be caused, for
example:
R by wearing clothing made from synthetic
fibers
R due to friction between clothing and seats
R if you push or pull the battery across the
carpet or other synthetic materials
R if you wipe the battery with a cloth G
WARNING
During the charging process, a battery produ- ces hydrogen gas. If a short circuit occurs or
sparks are created, the hydrogen gas can
ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a
connected battery does not come into con-
tact with vehicle parts.
R Never place metal objects or tools on a bat-
tery.
R It is important that you observe the descri-
bed order of the battery terminals when
connecting and disconnecting a battery.
R When jump-starting, make sure that the
battery poles with identical polarity are
connected.
R It is particularly important to observe the
described order when connecting and dis-
connecting the jumper cables.
R Never connect or disconnect the battery
terminals while the engine is running. G
WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash battery acid immediately with water and seek medical attention. H
Environmental note Batteries contain dangerous
substances. It is against the
law to dispose of them with
the household rubbish. They
must be collected separately
and recycled to protect the
environment. Dispose of batteries in an
environmentally friendly
manner. Take discharged
batteries to a qualified spe-
cialist workshop or a special
collection point for used bat-
teries.
! Have the battery checked regularly at a
qualified specialist workshop.
Observe the service intervals in the Main-
tenance Booklet or contact a qualified spe-
cialist workshop for more information.
! You should have all work involving the
battery carried out at a qualified specialist
workshop. In the exceptional case that it is
necessary for you to disconnect the battery yourself, make sure that:
R you switch off the engine and remove the
SmartKey. On vehicles with KEYLESS-
GO, ensure that the ignition is switched
off. Check that all the indicator lamps in
the instrument cluster are off. Otherwise, electronic components, such as the
alternator, may be damaged.
R you first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps. 394
Battery (vehicle)Breakdown assistance
ventilation while charging and jump-starting.
Do not lean over a battery. G
WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash battery acid immediately with water and seek medical attention. G
WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery, gases can escape from the battery. There is a risk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
! Only use battery chargers with a maxi-
mum charging voltage of 14.8 V.
! Only
charge the battery using the jump-
starting connection point.
If, at low temperatures, the indicator lamps/
warning lamps in the instrument cluster do
not light up, it is highly likely that the dis-
charged battery has frozen. In this case you
may neither jump-start the vehicle nor charge the battery. The service life of a thawed-out
battery may be shorter. The starting charac-
teristics can be impaired, particularly at low
temperatures. Have the thawed-out battery
checked at a qualified specialist workshop.
Never charge a battery still installed in the
vehicle unless a battery charger unit
approved by Mercedes-Benz is being used. An
accessory battery charge unit specially adap- ted for Mercedes-Benz vehicles and tested
and approved by Mercedes-Benz is available.
It permits the charging of the battery in its
installed position. Contact an authorized
Mercedes-Benz Center for further informa-
tion and availability. Charge the battery in
accordance with the separate instructions for the battery charger. The jump-starting connection point is in the
engine compartment (Y
page 397).
Read the battery charger's operating instruc- tions before charging the battery.
X Open the hood.
X Connect the battery charger to the positive
terminal and ground point in the same
order as when connecting the donor bat-
tery in the jump-starting procedure
(Y page 397). 396
Battery (vehicle)Breakdown assistance