2011 MERCEDES-BENZ GLK-Class check engine light

ProblemPossible causes/consequences and M SolutionsThe engine is not
running smoothly and
is misfiring.
There is a malfunction in the engine electronics or a mechanical
component of the engine management system.
XOnly depress the accelerator pedal slightly.XHave the cause rectified immediately at a qualified specialist
workshop.
Otherwise, non-combusted fuel may get into the catalytic
converter and damage it.
The coolant
temperature gauge
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.
XStop as soon as possible and allow the engine and the coolant
to cool down.
XCheck the coolant level (Y page 234). Observe the warning
notes as you do so and add coolant if necessary.Automatic transmission
Important safety notes
GWarning
It is dangerous to shift AUTOTRONIC out of
parking position P or neutral position N if the
engine speed is higher than idle speed. If your
foot is not firmly on the brake pedal, the
vehicle could accelerate quickly forward or in
reverse. You could lose control of the vehicle
and hit someone or something. Only shift into
gear when the engine is idling normally and
when your right foot is firmly on the brake
pedal.
GWarning!
Keep in mind that turning off the engine alone
only will shift AUTOTRONIC into neutral
position N automatically.
Always shift AUTOTRONIC into park position
P before turning off the engine.
Otherwise the vehicle could roll away which
could result in an accident and/or serious
personal injury.
Selector lever
Overview of transmission positions
Selector lever
PPark position with selector lever lockRReverseNNeutralDDrive134Automatic transmissionDriving and parking
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Keep the driver's footwell clear of all
obstacles. If there are any floormats or
carpets in the footwell, make sure that the
pedals still have sufficient clearance.
During sudden driving or braking maneuvers,
the objects could get caught between the
pedals. You could then no longer brake or
accelerate. This could lead to accidents and
injury.
Coasting with the engine switched offGWarning!
There is no power assistance for the steering
and the brake when the engine is not running.
Steering and braking requires significantly
more effort and you could lose control of the
vehicle and cause an accident as a result.
Do not turn off the engine while the vehicle is
in motion.
Exhaust check
GWarning
Inhalation of exhaust gas is hazardous to your
health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and possible death.
Do not run the engine in confined areas (such
as a garage) which are not properly ventilated.
If you think that exhaust gas fumes are
entering the vehicle while driving, have the
cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one
window fully open at all times.
Certain engine systems are designed to keep
the level of poisonous components in exhaust
fumes within legal limits.
These systems only work optimally if they are
maintained exactly in accordance with the
manufacturer's specifications. For this
reason, all work on the engine must be carried
out by qualified and authorized Mercedes-
Benz technicians.
The engine settings must not be changed in
any circumstances. Furthermore, all specific
service work must be carried out at regular
intervals and in accordance with the
Mercedes-Benz service requirements. Details
can be found in the Service Booklet.
Brakes
Important safety notes
GWarning
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle
control. Your vehicle's ABS will not prevent
this type of loss of control.
GWarning
Make sure that you do not endanger other
road users when you apply the brakes.
Downhill gradients
! On long and steep gradients, you must
reduce the cargo on the brakes by shifting
to a lower gear in good time. This allows
you to take advantage of engine braking
and helps you to avoid overheating the
brakes and wearing them out excessively.
When you take advantage of engine
braking, a drive wheel may not turn for
some time, e.g. on a slippery road surface.
This could cause damage to the drive train.
Such damage is not covered by the
Mercedes-Benz warranty.
Heavy and light loads
GWarning
Depressing the brake pedal constantly results
in excessive and premature wear to the brake
pads.
It may also cause the brakes to overheat,
seriously impairing their effectiveness. It may
then not be possible to stop the vehicle in
sufficient time to avoid an accident.
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If the brakes have been subjected to a heavy
cargo, do not stop the vehicle immediately,
but drive on for a short while. This allows the
airflow to cool the brakes more quickly.
Wet roadsGWarning
After driving in heavy rain for some time
without applying the brakes or through water
deep enough to wet brake components, the
first braking action may be somewhat
reduced. You have to depress the brake pedal
more firmly. Maintain a safe distance from
vehicles 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
GWarning
The layer of salt on the brake discs and the
brake pads/linings may cause a delay in the
braking effect, resulting in a significantly
longer braking distance, which could lead to
an accident.
To avoid this danger, you should:
R occasionally brake carefully, without
putting other road users at risk, when you
are driving on salted roads. This helps to
remove any salt that may have started to
build up on the brake discs and the brake
pads/linings.
R maintain a greater distance to the vehicle
ahead and drive with particular care.
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are removed
from the brake discs.
Maintenance of the brakes
! If the red brake warning lamp lights up in
the instrument cluster and you hear a
warning tone while the engine is running,
the brake fluid level may be too low.
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. This work should be carried
out at an authorized Mercedes-Benz
Center.
All checks and maintenance work on the
brake system must be carried out at a
qualified specialist workshop. This work
should be carried out at an authorized
Mercedes-Benz Center.
Only install brake pads and use brake fluid
recommended by Mercedes-Benz.
GWarning
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that safe
braking is substantially impaired. This could
result in an accident.
! Vehicles with 4MATIC: a function or
performance test may only be carried out
on a two-axle dynamometer. If you are
planning to have the vehicle tested on such
a dynamometer, contact an authorized
Mercedes-Benz Center to obtain further
information first. Otherwise, the drive train
or the brake system may suffer damage.
! As the ESP ®
system operates
automatically, the engine and the ignition
must be switched off (SmartKey in position
0 or 1 in the ignition lock) when:
R testing the parking brake on a brake
dynamometer.
R you intend to have the vehicle towed with
the front or rear axle raised (not
permitted for vehicles with 4MATIC).
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Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
If your brake system is only subjected to
moderate loads, you should regularly test
your brake system's function by forcefully
depressing the brake pedal when driving at
high speed. This will give the brake pads
better grip.GWarning
Make sure that you do not endanger other
road users when you apply the brakes.
You can find a description of Brake Assist
(BAS) on ( Y page 62).
Parking brake
If you drive on wet roads or dirt-covered
surfaces, road salt and/or dirt could get into
the parking brake.
In order to prevent corrosion and a reduction
in the braking power of the parking brake,
observe the following:
R gently depress the parking brake from time
to time before beginning the journey.
R drive approximately 110 yd (100 m)
without exceeding a speed of 12 mph
(20 km/h).
GWarning!
While performing this procedure please
assure that the vehicle is stopped before
applying the parking brake. Otherwise the
rear wheels could lock up. You could lose
control of the vehicle and cause an accident.
In addition, the vehicle’s brake lights do not
light up when the parking brake is engaged.
Make sure not to endanger any other road
users when you engage the parking brake.
Driving on wet roads
Hydroplaning
If water has accumulated to a certain depth
on the road surface, there is a danger of
hydroplaning occurring, even if:
R you drive at low speeds
R the tires have adequate tread depth
For this reason, in the event of heavy rain or
in conditions in which hydroplaning can occur
you must drive in the following manner:
R Lower your speed
R Avoid ruts
R Brake carefully
Driving on flooded roads
! Do not drive through flooded areas.
Check the depth of any water before driving
through it. Drive slowly through standing
water. Otherwise, water may enter the
vehicle interior or the engine compartment.
This can damage the electronic
components in the engine or AUTOTRONIC.
Water can also be drawn in by the engine's
air suction nozzles and this can cause
engine damage.
Prevent water from entering the vehicle
interior or engine compartment. If you have
to drive through standing water, please note
that:
R the maximum permissible still water depth
is 12 in. (30 cm).
R you should drive no faster than at walking
pace.
Winter driving
Important safety notes
Have your vehicle winterproofed at a qualified
specialist workshop, e.g. at an authorized
Mercedes-Benz Center, at the onset of
winter.
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GWarning
Driving with the message Check Brake Fluid Level displayed can result in an accident. Have
your brake system checked immediately.
Do not add brake fluid before checking the brake system. Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot engine parts and the brake fluid catching fire. You can be
seriously burned.
Lights
i Display messages concerning LEDs:
This display message will only appear if all LEDs have failed.
Display messagesPossible causes/consequences and M Solutionsb
Check Left
Corner'g Lite
or
Right Corner'g LiteThe left or right-hand cornering light is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Check Left Low Beam
or
Check Right Low
BeamThe left or right-hand low-beam headlamp is faulty. XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Chk. Trailer Lt
Tail Lamp
or
Chk. Trailer Rt
Tail LampThe left or right-hand trailer tail light is faulty.XCheck whether you are permitted to change the bulb yourself.
or
XVisit a qualified specialist workshop.b
Check Trailer Lt.
Turn Sig.
or
Chk. Trailer Rt
Turn Sig.The left or right-hand trailer turn signal lamp is faulty.XCheck whether you are permitted to change the bulb yourself.
or
XVisit a qualified specialist workshop.b
Chk. Trailer Brake
LampThe trailer brake lamp is faulty.XCheck whether you are permitted to change the bulb yourself.
or
XVisit a qualified specialist workshop.Display messages183On-board computer and displaysBA 204.9 USA, CA Edition A 2011; 1; 6, en-USd2mwentsVersion: 3.0.3.62010-06-15T08:58:39+02:00 - Seite 183Z

Display messagesPossible causes/consequences and M Solutionsb
Check Rear Lt.
Sidemarker
or
Chk. Rear Rt
SidemarkerThe rear left or right side marker lamp is faulty.XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Chk. Lt. Day
Running Lite
or
Chk. Rt. Day
Running LiteThe left or right-hand daytime running lamp is defective.XCheck whether you are permitted to change the bulb yourself
( Y page 107).
or
XVisit a qualified specialist workshop.b
Active Headlamps
InoperativeThe active light function is faulty.XVisit a qualified specialist workshop.b
Malfunction See
Operator's ManualThe exterior lighting is faulty.XVisit a qualified specialist workshop.b
AUTO Lamps
InoperativeThe light sensor is faulty. The low-beam headlamps are switched
on.XUSA only: switch off the daytime driving lights in the on-board
computer ( Y page 172).XSwitch the lights on and off using the light switch.XVisit a qualified specialist workshop.b
Switch Off LightsThe lights are still switched on when you leave the vehicle. A
warning tone also sounds.XTurn the light switch to c.
Engine
Display messagesPossible causes/consequences and M Solutions+
Check Coolant
Level See
Operator's ManualThe coolant level is too low.XAdd coolant, observing the warning notes when doing so
( Y page 234).XIf coolant needs adding more often than usual, have the engine
coolant system checked at a qualified specialist workshop.186Display messagesOn-board computer and displays
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For your safety, we strongly recommend that you contact an authorized Mercedes-Benz Center
immediately to have the system checked. Otherwise the SRS may not be activated when needed
in an accident, which could result in serious or fatal injury, or it might deploy unexpectedly and
unnecessarily which could also result in injury.
Engine
ProblemPossible causes/consequences and M Solutions;
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
R the fuel system
The emission limit values may have been exceeded and the engine
may be breaking in emergency mode.XHave the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states/provinces, you are required by law to visit a
qualified specialist workshop as soon as the Check Engine
warning lamp lights up. If necessary, check whether this is the
case in the state/province you are in.
8
The yellow reserve fuel
warning lamp flashes
while the engine is
running.The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.XCheck that the fuel filler cap is correctly closed.XIf the fuel filler cap is not correctly closed: close the fuel filler
cap.XIf the fuel filler cap is closed: visit a qualified specialist
workshop.8
The yellow reserve fuel
warning lamp lights up
while the engine is
running.The amount of fuel in the tank has dropped into the reserve range.XRefuel at the nearest gas station.200Warning and indicator lamps in the instrument clusterOn-board computer and displays
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ProblemPossible causes/consequences and M Solutions?
The red coolant
warning lamp lights up
while the engine is
running and the coolant
temperature gauge is
at the start of the scale.The temperature sensor for the coolant temperature gauge is
faulty.
The coolant temperature is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.XPull 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.XEngage the parking brake.XConsult a qualified specialist workshop.?
The red coolant
warning lamp comes on
while the engine is
running.The coolant level is too low.
If the coolant level is correct, the airflow to the radiator may be
blocked or the electric radiator fan may be malfunctioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XAllow the engine and coolant to cool.XCheck the coolant level and add the coolant ( Y page 234).
Observe the warning notes.XIf the coolant needs adding more often than usual, have the
engine coolant system checked.XMake sure that the air supply to the radiator is not blocked, e.g.
by snow, slush or ice.XAt coolant temperatures below 248 ‡ (120 †), continue driving
to the next qualified specialist workshop.XAvoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-start driving.?
The red coolant
warning lamp comes on
while the engine is
running. A warning tone
also sounds.The coolant has exceeded a temperature of 248 ‡ (120 †). The
airflow to the radiator may be blocked or the coolant level may be
too low.
The engine is not being cooled sufficiently and may be damaged.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XAllow the engine and coolant to cool.GWarning
Driving when your engine is overheated can cause some fluids which may have leaked into the
engine compartment to catch fire. You could be seriously burned.
Steam from an overheated engine can cause serious burns which can occur just by opening the
engine hood. Stay away from the engine if you see or hear steam coming from it.
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