Display messages Possible causes/consequences and
0050 Solutions003D The battery is not being charged.
A warning tone also sounds.
Possible causes are:
R
a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
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 160).
X Open the hood.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue driving. The
engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is not damaged:
X Visit a qualified specialist workshop. 00B2
Check Engine Oil
At Next Refueling The engine oil level has dropped to the minimum level.
A warning tone also sounds.
X
Check the oil level when next refueling, at the latest
(Y page 301).
X If necessary, add engine oil ( Y page 301).
X Have the engine checked at a qualified specialist workshop if
engine oil needs to be added more often than usual.
! Avoid long journeys with too little engine oil. The engine will
otherwise be damaged.
Information on approved engine oils can be obtained from any
qualified specialist workshop or on the Internet at http://
bevo.mercedes-benz.com. 00B6
Fuel Level Low The fuel level has dropped into the reserve range.
X
Refuel at the nearest gas station. 00A8 There is only a very small amount of fuel in the fuel tank.
X
Refuel at the nearest gas station without fail. Display messages
245
On-board computer and displays Z
Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your
vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: ( Y page 27).ASSYST PLUS
Service messages
The ASSYST PLUS service interval display
informs you of the next service due date.
Information on the type of
service and service
intervals (see the separate Maintenance
Booklet).
You can obtain further information from an
authorized Mercedes-Benz Center or at
http://www.mbusa.com (USA only).
i The ASSYST PLUS service interval display
does not show any information on the
engine oil level. Observe the notes on the
engine oil level ( Y page 300).
The multifunction display shows a service
message for several seconds, e.g.:
R Next Service A in .. days
R Service A Due
R Service A Exceeded by .. days
Depending on the operating conditions of the
vehicle, the remaining time or distance until
the next service due date is displayed.
The letter A or B, possibly in connection with
a number or another letter, shows the type of
service. A stands for a minor service and B for
a major service.
You can obtain further information from an
authorized Mercedes-Benz Center. The ASSYST PLUS service interval display
does not take into account any periods of
time during which the battery is
disconnected.
Maintaining the time-dependent service
schedule:
X
Note down the service due date displayed
in the multifunction display before
disconnecting the battery.
or
X After reconnecting the battery, subtract
the battery disconnection periods
from
the
service date shown on the display. Hiding a service message
X Press the 0038 or 0076 button on the
steering wheel. Displaying service messages
X Switch on the ignition.
X Press the 0059 or 0065 button on the
steering wheel to select the Serv. menu.
X Press the 0063
or 0064 button to
select the
ASSYST PLUS submenu and confirm with
0076.
The service due date appears in the
multifunction display. Information about Service
Resetting the ASSYST PLUS service
interval display !
If the ASSYST PLUS service interval
display has been inadvertently reset, this
setting can be corrected at a qualified
specialist workshop.
Have service work carried out
as described
in the Maintenance Booklet. This may
otherwise lead to increased wear and
damage to the major assemblies or the
vehicle. 298
ASSYST PLUS
Maintenance and care
A qualified specialist workshop, e.g. an
authorized Mercedes-Benz Center, will reset
the ASSYST PLUS service interval display
after the service work has been carried out.
You can also obtain further information on
maintenance work, for example.
Special service requirements
The specified maintenance interval takes only
the normal operation of the vehicle into
account. Under arduous operating
conditions
or increased load on the vehicle,
maintenance work must be carried out more
frequently, for example:
R regular city driving with frequent
intermediate stops
R if the vehicle is primarily used to travel
short distances
R use
in mountainous terrain or on poor road
surfaces
R if the engine is often left idling for long
periods
Under these or similar conditions, have, for
example, the air filter, engine oil and oil filter
replaced or changed more frequently. Under
arduous operating conditions, the tires must
be checked more often. Further information
can be obtained at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
Center.
Driving abroad An extensive Mercedes-Benz Service network
is also available in other countries. You can
obtain further information from any
authorized Mercedes-Benz Center. Engine compartment
Hood
Important safety notes G
WARNING
If the hood is unlatched, it may open up when
the vehicle is in motion and block your view.
There is a risk of an accident.
Never unlatch the hood while driving. G
WARNING
When opening and closing the hood, it may
suddenly fall into the closed
position. There is
a risk of injury to persons within range of
movement of the hood.
Open and close the hood only when no one is
within its range of movement. G
WARNING
Certain components in the engine
compartment, such as the engine, radiator
and parts of the exhaust
system, can become
very hot. Working in the engine compartment
poses a risk of injury.
Where possible, let the engine cool down and
touch only the components described in the
following. G
WARNING
Opening the hood when the engine is
overheated or when there is a fire in the
engine compartment could
expose you
to hot
gases or other service products. There is a
risk of injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department. G
WARNING
The engine compartment contains moving
components. Certain components, such as
the radiator fan, may continue to run or start
again suddenly when
the ignition
is off. There
is a risk of injury. Engine compartment
299
Maintenance and care
Z
If you need to do any work inside the engine
compartment,
R
switch off the ignition
R never reach into the area where there is a
risk of danger from moving components,
such as the fan rotation area
R keep clothing away from moving parts G
WARNING
The ignition system and the fuel injection
system work under high voltage.
If you touch
components which are under voltage, you
could get an electric shock. There is a risk of
injury.
Never touch components of the ignition
system or fuel injection system when the
ignition is switched on.
Opening the hood G
WARNING
The windshield wipers and wiper linkage
could be set in motion.
When the hood is open, you or others could
be injured by the wiper linkage.
Make sure that the windshield wipers are
switched off. Remove the SmartKey or make
sure that no ignition position has been
selected with KEYLESS-GO. All indicator
lamps must be off in the instrument panel.
! Make sure that
the windshield
wipers are
not folded away from the windshield. You
could otherwise damage the windshield
wipers or the hood.
X Make sure that the windshield wipers are
turned off. X
Pull release lever 0043 on the hood.
The hood is released. X
Reach into the gap, pull hood catch
handle 0044 up and lift the hood.
If you lift the hood by approximately
15 inches (40 cm
), the
hood is opened and
held open automatically by the gas-filled
strut.
Closing the hood X
Lower the hood and let it fall from a height
of approximately 8 in (20 cm).
X Check that the hood
has engaged properly.
If the hood can be raised slightly, it is not
properly engaged. Open it again and close
it with a little more force. Engine oil
General notes on the oil level Depending on the driving style, the vehicle
consumes up to 0.9 US qt
(0.8 liters) of oil
over a
distance of
600 miles (1,000 km). The300
Engine compartment
Maintenance and care
oil consumption may be higher than this when
the vehicle is new
or
if you frequently drive at
high engine speeds.
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 a diesel engine
X
Park the vehicle on a level surface. To check the oil level with the engine at
operating temperature, switch the engine
off
and wait for
approximately
five minutes.
X Pull oil dipstick 0043 out of the dipstick
guide
tube.
X Wipe off oil dipstick 0043.
X Slowly slide oil dipstick 0043 into the guide
tube to the stop, and take it out again.
If the level is between MIN mark 0087 and
MAX mark 0044, the oil level is correct.
X If the oil level has dropped to MIN mark
0087 or below, add 1.1 US qt (1.0 liter) of
engine oil.
Adding engine oil G
WARNING
If engine oil comes into contact with hot
components in the engine compartment, it
may ignite. There is a risk of fire and injury.
Make sure that engine oil is not spilled next
to the filler neck. Let the engine cool down
and thoroughly clean the engine oil off the
components before starting the engine. H
Environmental note
When adding oil, take care not to spill any. If
oil enters the soil or waterways, it is harmful
to the environment.
! Only use engine oils and oil filters that
have been approved for vehicles with a
service system. You can obtain
a list of the
engine oils and oil filters tested and
approved in accordance with the
Mercedes-Benz Specifications for Service
Products at any Mercedes-Benz Service
center. Engine compartment
301
Maintenance and care Z
Damage to the engine or exhaust system is
caused by the following:
R
using engine oils and oil
filters that have
not been specifically approved for the
service system
R replacing engine oil and oil filters after
the interval for replacement specified by
the service system has been exceeded
R using engine oil additives.
! Do not add too much oil. If the oil level is
above the "max" mark on the dipstick, too
much oil has been added. This can lead to
damage to the engine or the catalytic
converter. Have excess oil siphoned off. Example: engine oil cap
X
Turn cap 0043 counter-clockwise and remove
it.
X Add engine oil.
If the oil level is at or below the MIN mark
on the oil dipstick, add
1.1 US qt (1.0 liter)
of engine oil.
X Replace cap 0043 on the filler neck and turn
clockwise.
Ensure that the cap locks into place
securely.
X Check the oil level again with the oil
dipstick (Y page 301).
Further information on engine oil
(Y page 369). Checking and adding other service
products
Checking coolant level G
WARNING
The engine cooling system is pressurized,
particularly when the engine is warm. When
opening the cap, you could
be scalded by hot
coolant spraying out. There is a risk of injury.
Let the engine cool down before opening the
cap. Wear eye and hand protection when
opening the cap. Open the cap slowly half a
turn to allow pressure to escape.
Only check the coolant level when the vehicle
is on a level surface and the engine has cooled
down.
X Turn the SmartKey to position 2 in the
ignition lock (Y page 141).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y
page 141).
X Check the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
158 ‡ (70 †). X
Slowly turn cap 0043 half a turn counter-
clockwise and allow excess pressure to
escape.
X Turn cap 0043 further
counter-clockwise and
remove it.
If the coolant is at the level of marker bar
0087 in the filler neck when cold, there is
enough coolant in coolant expansion
tank 0044
.302
Engine compartment
Maintenance and care
H
Environmental note
Dispose of service products in an
environmentally responsible manner.
Service products include the following:
R Fuels (e.g. gasoline, diesel)
R Exhaust gas aftertreatment additives, e.g.
DEF
R Lubricants (e.g. engine oil, transmission
oil)
R Coolant
R Brake fluid
R Windshield washer fluid
R Climate control system refrigerant
Comply with all valid regulations with respect
to handling, storing, and disposing of service
fluids.
Components and service products must be
matched. You should therefore only use
products that have been tested and approved
by Mercedes-Benz.
Information about tested and approved
products can be obtained from an authorized
Mercedes-Benz Center or on the Internet at
http://bevo.mercedes-benz.com.
You can recognize service products approved
by Mercedes-Benz by the following
inscription on the containers:
R MB-Freigabe (e.g. MB-Freigabe 229.51)
R MB Approval (e.g. MB Approval 229.51)
Other designations or recommendations
indicate a level of quality or a specification in
accordance with an MB Sheet number (e.g.
MB 229.5). They have not necessarily been
approved by Mercedes-Benz. Fuel
Important safety notes G
WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and
explosion. You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable, the
auxiliary
heating before
refueling. G
WARNING
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:
R Wash away fuel from skin immediately
using soap and water.
R If fuel comes into contact with your eyes,
immediately rinse them thoroughly with
clean water. Seek medical assistance
without delay.
R If fuel is swallowed, seek medical
assistance without delay. Do not induce
vomiting.
R Immediately change out of clothing which
has come into contact with fuel.
Tank capacity Model Total
capacity GLK 250 BlueTEC
15.6 US gal
(59.0 l) All other models
17.4 US gal
(66.0 l) Model Of which
reserve All models
approx.
2.1 US gal (8.0 l)366
Service products and filling capacities
Technical data
Gasoline
Fuel grade
!
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. The repair
costs are high. Notify a qualified specialist
workshop and have the fuel tank and fuel
lines drained completely.
! You should only refuel with unleaded
premium-grade gasoline as this avoids
damaging the catalytic converter.
If engine running problems are apparent,
have the cause checked immediately and
repaired. Excess unburned fuel can
otherwise enter the catalytic converter,
leading to overheating and possibly
causing a fire.
! To ensure the longevity and full
performance of the engine, only premium-
grade unleaded gasoline may be used.
If there is no premium-grade unleaded
gasoline available and regular unleaded
gasoline must be used, please observe the
following precautions:
R only fill the fuel tank to half full with
regular unleaded gasoline and fill the rest
with premium-grade unleaded gasoline
as soon as possible.
R do not drive at the maximum speed.
R avoid sudden acceleration.
R if the vehicle is carrying a light load, e.g.
two passengers without luggage, do not
allow the engine to rev above 3000 rpm.
R if the vehicle is fully loaded or is being
operated in mountainous terrain, do not
depress the accelerator pedal further
than 00C3 of the pedal travel.
Only refuel using premium-grade unleaded
gasoline with a minimum octane rating of 91. Reformulated Gasoline (RFG) and/or
unleaded
gasoline
with additives
can
be used.
The concentration of additives in the fuel,
however, must not exceed 10%, e.g.:
R Ethanol
R TAME
R ETBE
R IPA
R TBA
For MTBE, the concentration should not
exceed 15%.
The concentration of methanol in gasoline,
including other additives, must not exceed
3%.
Using mixtures of methanol and ethanol is not
permitted. Gasohol, a mixture of 10% ethanol
and 90% unleaded gasoline may be used.
All of these blends must fulfill the fuel
requirements, e.g.:
R knock resistance
R boiling point
R vapor pressure
You will usually find information about the fuel
grade on the pump. If you cannot find the
label on the pump, ask the staff for
assistance.
i For more information, contact a qualified
specialist workshop.
Information on refueling (Y page 154).
Additives
! Operating the engine with fuel additives
can increase wear and tear to the fuel
system high-pressure pump and lead to
contamination of the entire fuel system.
The repair costs are high. This does not
include additives for the removal and
prevention of residue buildup. gasoline
must only be mixed with additives
recommended by Mercedes-Benz. More
information about recommended additives
can be obtained from any authorized
Mercedes-Benz Center. Service products and filling capacities
367
Technical data Z