check engine MERCEDES-BENZ GLK SUV 2012 Owner's Guide

Engine (12-button multifunction steering wheel)
Display messages Possible causes/consequences and
M
MSolutions +
Top Top
up upcoolant
coolant See
See
Owner's Manual
Owner's Manual 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.
X Top up the coolant, observing the warning notes before doing
so (Y page 316).
X If the coolant needs topping up more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop. ? The fan motor is faulty.
X
If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start traffic. ?
Coolant Stop vehi‐ Coolant Stop vehi‐
cle Switch engine cle Switch engine
off off The coolant is too hot.
A warning tone also sounds.
G WARNING
Never drive with an overheated engine. Driving when your engine
is overheated can cause some fluids which may have leaked into
the engine compartment to catch fire.
Steam from an overheated engine can cause serious burns, which
can occur just by opening the bonnet.
There is a risk of injury.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 164).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Do not start the engine again until the display message goes out
and the coolant temperature is below 120 †. The engine may
otherwise be damaged.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately.
Under normal operating conditions and with the specified coolant
level, the coolant temperature may rise to 120 †. Display messages
267On-board computer and displays Z

Display messages Possible causes/consequences and
M
MSolutions # The battery is not being charged.
A warning tone also sounds.
Possible causes:
R
faulty alternator
R torn poly-V-belt
R a malfunction in the electronics
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away ( Ypage 164).
X Open the bonnet.
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 OK:
X Visit a qualified specialist workshop. 4
Check eng. oil Check eng. oil
lev. when next lev. when next
refuelling refuelling The engine oil level has dropped to the minimum level.
A warning tone also sounds.
X
Check the oil level when next refuelling, at the latest
(Y page 315).
X If necessary, top up the engine oil (Y page 316).
X Have the engine checked at a qualified specialist workshop if
the engine oil needs topping up more often than usual. 8
Reserve fuel level Reserve fuel level The fuel level has dropped into the reserve range.
Operation of the auxiliary heating is deactivated if the fuel level
drops into the reserve range.
X
Refuel at the nearest filling station. C There is only a very small amount of fuel in the fuel tank.
The auxiliary heating cannot be operated.
X
Refuel at the nearest filling station without fail. ¸
Please Please
replace
replace air
air
filter
filter Vehicles with a diesel engine: the engine air filter is dirty and must
be replaced.
X
Visit a qualified specialist workshop. 268
Display
messagesOn-board computer and displays

Display messages Possible causes/consequences and
M
MSolutions !
Clean Clean
the
thefuel
fuel fil‐
fil‐
ter
ter Vehicles with a diesel engine: there is water in the fuel filter. The
water must be drained off.
X
Visit a qualified specialist workshop. ¯
Refill AdBlue at Refill AdBlue at
workshop See Own‐ workshop See Own‐
er's Manual er's Manual The AdBlue
®
level has fallen below the reserve range. A warning
tone also sounds.
X Have AdBlue ®
refilled as soon as possible at a qualified spe-
cialist workshop. ¯
Refill AdBlue at Refill AdBlue at
workshop No start workshop No start
in .. km in .. km The AdBlue
®
level is only sufficient for the indicated distance. A
warning tone also sounds.
X Have AdBlue ®
refilled as soon as possible at a qualified spe-
cialist workshop. ¯
Refill AdBlue at Refill AdBlue at
workshop Eng. workshop Eng.
start not possible start not possible The AdBlue
®
tank is empty. A warning tone also sounds. You can
no longer start the engine.
X Consult a qualified specialist workshop immediately. ¯
Check AdBlue See Check AdBlue See
Owner's Manual Owner's Manual The AdBlue
®
system is malfunctioning. A warning tone also
sounds.
X Visit a qualified specialist workshop. ¯
Eng. Eng.
start
start not
notpos‐
pos‐
sible in ... km
sible in ... km The AdBlue
®
system is malfunctioning. A warning tone also
sounds.
X Visit a qualified specialist workshop immediately. ¯
Eng. Eng.
start
start not
notpos‐
pos‐
sible
sible The AdBlue
®
system is malfunctioning. A warning tone also
sounds. You can no longer start the engine.
X Consult a qualified specialist workshop immediately. Display
messages
269On-board computer and displays Z

Display messages Possible causes/consequences and
M
MSolutions Pwr. steering
Pwr. steering
malfunction malfunction The power steering assistance is faulty.
A warning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a risk of an accident.
X Check whether you are able to apply the extra force required.
X If you are able to steer safely: carefully drive on to a qualified
specialist workshop.
X If you are unable to steer safely: do not drive on. Contact the
nearest qualified specialist workshop. Top up Top up
washer fluid washer fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
X
Top up the washer fluid ( Ypage 317). Vehicle (12-button multifunction steering wheel)
Display messages Possible causes/consequences and
M MSolutions To start engine,
To start engine,
shift to either P shift to either P
or N or N You have attempted to start the engine with the transmission in
position
Ror D.
X Shift the transmission to position Por N. P P
Select Park (P) Select Park (P) You have switched off the engine with the Start/Stop button and
opened the driver's door.
You wanted to lock the vehicle.
A warning tone also sounds.
or
You have switched off the engine with the Start/Stop button and
opened the driver's door with the transmission in position N.
X Shift the transmission to position P.A The tailgate is open.
G WARNING
When the engine is running, exhaust gases can enter the vehicle
interior if the tailgate is open.
There is a risk of poisoning.
X Close the tailgate. Display
messages
279On-board computer and displays Z

Problem Possible causes/consequences and
M
MSolutions ֊
The yellow ESP
®
warn-
ing lamp flashes while
the vehicle is in motion. ESP
®
or traction control has intervened because there is a risk of
skidding or at least one wheel has started to spin.
Cruise control or DISTRONIC PLUS is deactivated.
X Only depress the accelerator pedal as far as necessary when
pulling away.
X Accelerate more gently while the vehicle is in motion.
X Adapt your driving style to suit the road and weather conditions.
X Do not deactivate ESP ®
.
Exceptions: (Y page 67) å
The yellow ESP
®
OFF
warning lamp is lit while
the engine is running. ESP
®
is deactivated.
G WARNING
If ESP ®
is switched off, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Reactivate ESP ®
.
Exceptions: (Y page 67)
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Drive on carefully.
X Have ESP ®
checked at a qualified specialist workshop. ÷äå
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
, BAS, BAS PLUS, PRE-SAFE ®
, PRE-SAFE ®
Brake, the HOLD
function, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation are not available due to a malfunction.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above.
The braking distance in an emergency braking situation can thus
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
289On-board computer and displays Z

Problem Possible causes/consequences and
M
MSolutions J
The red brake system
warning lamp comes on
while the vehicle is
moving. A warning tone
also sounds.
You are driving with the parking brake applied.
X
Release the parking brake.
The warning lamp goes out and the warning tone ceases. 6
The red SRS warning
lamp is lit while the
engine is running.
There is a malfunction in the SRS (Supplemental Restraint Sys-
tem).
G WARNING
The airbags or belt tensioners may either be triggered uninten-
tionally or, in the event of an accident, may not be triggered.
This poses an increased risk of injury.
X Drive on carefully.
X Have SRS checked at a qualified specialist workshop immedi-
ately.
For further information about the Supplemental Restraint System,
see (Y page 43). Engine
Problem Possible causes/consequences and
M MSolutions ;
The yellow engine diag-
nostics warning lamp
lights up while the
engine is running.
There may be a fault, 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 petrol engines)
R in the fuel system
The emission limit values may be exceeded and the engine may
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop. Vehicles with a diesel engine: the fuel tank has been run dry
(Y
page 163).
X Start the engine three to four times after refuelling.
If the yellow engine diagnostics warning lamp goes out, emer-
gency running mode is cancelled. The vehicle need not be
checked. Warning and indicator lamps in the instrument cluster
291On-board computer and displays Z

Problem Possible causes/consequences and
M
MSolutions ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator
may be blocked or the electric engine radiator fan may be mal-
functioning.
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 Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Let the engine and coolant cool down.
X Check the coolant level and top up the coolant (Y page 316).
Observe the warning notes as you do so.
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start traffic. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 120 †. The airflow to the
engine radiator may be blocked or the coolant level may be too
low.
The engine is not being cooled sufficiently and may be damaged.
X
Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Let the engine and coolant cool down.
X Check the coolant level and top up the coolant (Y page 316).
Observe the warning notes as you do so.
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving in
mountainous terrain and stop-start traffic. Warning and indicator lamps in the instrument cluster
293On-board computer and displays Z

Have service work carried out as described
in the Service Booklet. This may otherwise
lead to increased wear and damage to the
major assemblies or the vehicle.
A qualified specialist workshop, e.g. a
Mercedes-Benz Service Centre, will reset the
ASSYST PLUS service interval display after
the service work has been carried out. You
can also obtain further information on main-
tenance work, for example.
Special service requirements
Arduous operating conditions or increased
loads on the vehicle will require some service
work to be performed more often than for a
vehicle in normal use. Such arduous condi-
tions include regular city driving with frequent
intermediate stops and use in mountainous
terrain or on poor road surfaces.
For example, if the vehicle is used under ardu-
ous operating conditions, have air filters,
engine oil and oil filters changed frequently
and check the wheels often. Further informa-
tion can be obtained at a qualified specialist
workshop, e.g. a Mercedes-Benz Service
Centre.
Driving abroad
An extensive Mercedes-Benz Service network
is also available in other countries. The
Service Hotline's current telephone numbers
for use when you are abroad are to be found
in the "Mercedes-Benz Service24h" section
of the Service Booklet. AdBlue
®
service display
i For BlueTEC vehicles only.
To function properly, BlueTEC exhaust gas
aftertreatment must be operated with the
reducing agent AdBlue ®
. AdBlue ®
is topped
up as part of the service. Under normal oper-
ating conditions, a full tank of AdBlue ®
should
last until the next service due date.
Depending on how and where the vehicle is
used, there may be an increase in the AdBlue
®
consumption, resulting in the next
service due date being brought forward.
Certain display messages show that
AdBlue ®
must be topped up, e.g.
Refill AdBlue at workshop See Own‐
Refill AdBlue at workshop See Own‐
er's Manual er's Manual
Refill AdBlue at workshop No start Refill AdBlue at workshop No start
in .. km in .. km
A warning tone also sounds.
You can no longer start the engine when the
AdBlue ®
supply has been used up.
R 4-button multifunction steering wheel
(Y page 266)
R 12-button multifunction steering wheel
(Y page 269)
! Have the AdBlue ®
tank topped up at a
qualified specialist workshop only. The
vehicle may otherwise be damaged or
soiled.
Before taking a trip with your vehicle outside
Europe, have the AdBlue ®
supply checked at
a qualified specialist workshop. If necessary,
have AdBlue ®
topped up. Before a longer stay
outside of Europe, consult a qualified special-
ist workshop.
Observe the notes on AdBlue ®
(Y page 368).
You can obtain further information about
BlueTEC exhaust gas aftertreatment and
AdBlue ®
from any Mercedes-Benz Service
Centre. Engine compartment
Bonnet
Opening the bonnet G
WARNING
Do not pull the release lever while the vehicle
is in motion. If you do so, the bonnet may open
up and block your view. Engine compartment
313Maintenance and care Z

Closing the bonnet
G
WARNING
Make sure that nobody can become trapped
as you close the bonnet.
X Lower the bonnet and let it fall from a
height of approximately 20 cm.
X Check that the bonnet has engaged prop-
erly.
If the bonnet can be raised slightly, it is not
properly engaged. Open it again and close
it with a little more force. Radiator
Vehicles with a diesel engine: do not cover
the radiator. Do not use thermal mats, insect
protection covers or anything similar. Doing
so can cause the Onboard Diagnostics Sys-
tem to display inaccurate values. Some of
these values are legally required and must
always be correct. Engine oil
General notes on oil level Depending on your driving style, the vehicle
consumes up to 0.8 l of oil per 1,000 km. The
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 installed at 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 dip-
stick Example: vehicles with a petrol engine
Example: vehicles with a diesel engine
X
Park the vehicle on a level surface.
To check the oil level with the engine at
normal operating temperature, switch the
engine off and wait for approximately five
minutes.
X Pull oil dipstick :out of the oil dipstick
tube.
X Wipe off oil dipstick :.
X Slowly 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.
X If the oil level has dropped to MIN mark
= or below, add 1.0 litre of engine oil. Engine compartment
315Maintenance and care Z

Adding engine oil
G
WARNING
If engine oil comes into contact with hot
engine parts, it may ignite and you could burn
yourself. Do not spill any engine oil on hot
engine parts. H
Environmental note
When topping up the 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
Centre.
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 changing the engine oil and oil filter after
missing the change interval required by
the service system
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 con-
verter. Have excess oil siphoned off. Example: engine oil filler cap
X
Turn cap :anti-clockwise and remove it.
X Top up the engine oil.
If the oil level is at or below the MIN mark
on the oil dipstick, add 1.0 litre of engine
oil.
X Replace cap :on the filler neck and turn
clockwise.
Make sure that the cap locks securely into
place.
X Check the oil level again with the oil dip-
stick (Y page 315).
For further information on engine oil, see
(Y page 369). Checking and adding other service
products
Checking the coolant level G
WARNING
The cooling system is pressurised. Therefore,
only unscrew the cap once the engine has
cooled down. The coolant temperature gauge
must display less than 70 † . Otherwise, you
could be scalded if hot coolant escapes.
Only check the coolant level if the vehicle is
on a level surface and the engine has cooled
down.
X Turn the key to position 2(Y page 147) in
the ignition lock. 316
Engine compartmentMaintenance and care