check engine light MERCEDES-BENZ GLK-CLASS SUV 2015 User Guide

Starting the engine
Important safety notes
GWARNING
If children are left unsupervised in the vehicle, they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children.
GWARNING
Combustion engines emit poisonous exhaust
gases such as carbon monoxide. Inhaling
these exhaust gases leads to poisoning. There is a risk of fatal injury. Therefore never leave
the engine running in enclosed spaces with-
out sufficient ventilation.
GWARNING
Flammable materials introduced through
environmental influence or by animals can
ignite if in contact with the exhaust system orparts of the engine that heat up. There is a risk
of fire.
Carry out regular checks to make sure that
there are no flammable foreign materials in
the engine compartment or in the exhaust
system.
! Do not depress the accelerator when
starting the engine.
General notes
iVehicles with a gasoline engine: the
catalytic converter is preheated for up to
30 seconds after a cold start. The sound of the engine may change during this time.
Automatic transmission
X Shift the transmission to position P.
The transmission position display in the
multifunction display shows P.
iYou can also start the engine when the
transmission is in position N.
Starting procedure with the SmartKey
iTo start the engine using the SmartKey
instead of KEYLESS-GO, pull the Start/
Stop button out of the ignition lock.
X To start a gasoline engine: turn the
SmartKey to position 3 in the ignition lock
( Y page 149) and release it as soon as the
engine is running.
X To start a diesel engine: turn the Smart-
Key to position 2 in the ignition lock
( Y page 149).
The % preglow indicator lamp in the
instrument cluster lights up.
X When the % preglow indicator lamp
goes out, turn the SmartKey to position 3
( Y page 149) and release it as soon as the
engine is running.
iYou can start the engine without preglow
if the engine is warm.
Using KEYLESS-GO to start the engine
You can start the engine if a valid SmartKey
with the integrated KEYLESS-GO function is in the vehicle. Always take the SmartKey with
you when leaving the vehicle, even if you only
leave it for a short time. Pay attention to the
important safety notes.
iThe Start/Stop button can be used to
start the vehicle without inserting the
SmartKey into the ignition lock. The Start/
Driving151
Driving and parking
Z

ProblemPossible causes/consequences and M Solutions
The engine is not run-
ning smoothly and is
misfiring.There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
X Only depress the accelerator pedal slightly.
X Have the cause rectified immediately at a qualified specialist
workshop.
Otherwise, non-combusted fuel may get into the catalytic con-
verter and damage it.
The coolant tempera-
ture 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.
X Stop as soon as possible and allow the engine and the cool ant to
cool down.
X Check the coolant level ( Y page 303). Observe the warning
notes as you do so and add coolant if necessary.
Automatic transmission
Important safety notes
GWARNING
If the engine speed is above the idling speed
and you engage transmission position D or R,
the vehicle could pull away suddenly. There is a risk of an accident.
When engaging transmission position D or R,
always firmly depress the brake pedal and do not simultaneously accelerate.
GWARNING
The automatic transmission switches to neu-
tral position N when you switch off the engine.
The vehicle may roll away. There is a risk of an
accident.
After switching off the engine, always switch
to parking position P. Prevent the parked vehi-
cle from rolling away by applying the parking
brake.
DIRECT SELECT lever
Overview of transmission positions
The DIRECT SELECT lever is on the right of the
steering column.
jPark position with parking lock
kReverse gear
iNeutral
hDrive
iThe DIRECT SELECT lever always returns
to its original position. The current trans-
mission position P, R , N or D appears in the
transmission position display in the multi-
function display ( Y page 157).
156Automatic transmission
Driving and parking

Opening the fuel filler flap
:To open the fuel filler flap
;To insert the fuel filler cap
=Tire pressure table
?Fuel type to be used
X Switch the engine off.
X Remove the SmartKey from the ignition
lock.
X KEYLESS-GO: open the driver’s door.
This corresponds to SmartKey position 0:
"SmartKey removed".
The driver’s door can be closed again.
X Press the fuel filler flap in the direction of
arrow :.
The fuel filler flap opens slightly.
X Open the fuel filler flap fully.
X Turn the fuel filler cap counterclockwise
and remove it.
X Insert the fuel filler cap into the holder
bracket on the inside of fuel filler flap ;.
X Completely insert the filler neck of the fuel
pump nozzle into the tank, hook in place
and refuel.
X Only fill the tank until the pump nozzle
switches off.
iVehicles with a diesel engine: the filler
neck is designed for refueling at diesel fill-
ing pumps.
iDo not add any more fuel after the pump
stops filling for the first time. Otherwise,
fuel may leak out.
Closing the fuel filler flap
X Replace the cap on the filler neck and turn
clockwise until it engages audibly.
X Close the fuel filler flap.
iClose the fuel filler flap before locking the
vehicle.
iIf you are driving with the fuel filler cap
open, the 8 reserve fuel warning lamp
flashes. A message appears in the multi-
function display ( Y page 248).
In addition, the ; Check Engine warning
lamp may light up ( Y page 267).
For further information on warning and indi- cator lamps in the instrument cluster, see
( Y page 267).
164Refueling
Driving and parking

Braking
Important safety notes
GWARNING
If you shift down on a slippery road surface in an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on a slippery road surface.
Downhill gradients
! On long and steep gradients, you must
reduce the load on the brakes by shifting
early to a lower gear. This allows you to take advantage of the engine braking effect and
helps avoid overheating and excessive
wear of the brakes.
When you take advantage of the engine
braking effect, a drive wheel may not turn
for some time, e.g. on a slippery road sur-
face. This could cause damage to the drive train. This type of damage is not covered bythe Mercedes-Benz warranty.
Heavy and light loads
GWARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This increases the stopping distance and can even
cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If the brakes have been subjected to a heavy load, do not stop the vehicle immediately.
Drive on for a short while. This allows the air-
flow to cool the brakes more quickly.
Wet roads
If you have driven for a long time in heavy rain without braking, there may be a delayed reac-
tion from the brakes when braking for the first time. This may also occur after the vehicle has
been washed.
You have to depress the brake pedal more
firmly. Maintain a greater distance from the
vehicle in front.
After driving on a wet road or having the vehi- cle washed, brake firmly while paying atten-
tion to the traffic conditions. This will warm up
the brake discs, thereby drying them more
quickly and protecting them against corro-
sion.
Limited braking performance on salt-
treated roads
If you drive on salted roads, a layer of salt
residue may form on the brake discs and
brake pads. This can result in a significantly
longer braking distance. R Brake occasionally to remove any possible
salt residue. Make sure that you do not
endanger other road users when doing so.
R Carefully depress the brake pedal and the
beginning and end of a journey.
R Maintain a greater distance to the vehicle
ahead.
Servicing the brakes
! If the red brake warning lamp lights up in
the instrument cluster and you hear a warn-
ing tone while the engine is running, the
brake fluid level may be too low. Observe
additional warning messages in the multi-
function display.
The brake fluid level may be too low due to brake pad wear or leaking brake lines.
Have the brake system checked immedi-
ately. This work should be carried out at a
qualified specialist workshop.
All checks and maintenance work on the
brake system must be carried out at a quali-
172Driving tips
Driving and parking

are indicated by the flashing of red warning
lamp :. There are no further warning tones.
Switching on Blind Spot Assist X Make sure that Blind Spot Assist
(Y page 229) is activated in the on-board
computer.
X Turn the SmartKey to position 2 in the igni-
tion lock.
Warning lamps : in the exterior mirrors
light up red for approximately 1.5 seconds
and then turn yellow.
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical connec-
tion. This can be accomplished by checking
the trailer lighting. In this event, Blind Spot
Assist is deactivated. The indicator lamp
lights up yellow in the exterior mirrors and the
Blind Spot Assist Currently UnavailZ
able See Operator's Manual message
appears in the multifunction display.
iYou can deactivate the indicator lamps in
the exterior mirrors.
To do so, switch off Blind Spot Assist when:
R the SmartKey is in position 2 in the igni-
tion lock
R the engine is not running
R the electrical connection to the trailer
has been established
Lane Keeping Assist
General notes
Lane Keeping Assist monitors the area in
front of your vehicle with camera :, which is
mounted at the top of the windshield. Lane
Keeping Assist detects lane markings on the
road and warns you before you leave your
lane unintentionally.
:Active Lane Keeping Assist camera
If you select
km on the on-board computer in
the
Display Unit Speed-/Odometer func-
tion ( Y page 230), Lane Keeping Assist is
active starting at a speed of 60 km/h. If the
miles display unit is selected, the assistance
range begins at 40 mph.
A warning may be given if a front wheel
passes over a lane marking. It will warn you by
means of intermittent vibration in the steer-
ing wheel for up to 1.5 seconds.
Important safety notes
If you fail to adapt your driving style, Lane
Keeping Assist can neither reduce the risk of
an accident nor override the laws of physics. Lane Keeping Assist cannot take into accountthe road, traffic and weather conditions. Lane
Keeping Assist is merely an aid. You are
responsible for the distance to the vehicle in
front, for vehicle speed, for braking in good
time and for staying in your lane.
GWARNING
Lane Keeping Assist may not always clearly
recognize lane markings.
In this case, Lane Keeping Assist may:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and stay in lane, in particular if
warned by Lane Keeping Assist.
Driving systems205
Driving and parking
Z

Display messagesPossible causes/consequences and M Solutions
b
Check Left Daytime
Running
Light or Check
Right Daytime RunZ
ning Light
The left or right-hand daytime running lamp is faulty.
X Visit a qualified specialist workshop.
b
Active Light SysZ
tem Inoperative
The active light function is faulty.
X Visit a qualified specialist workshop.
b
Malfunction See
Operator's Manual
The exterior lighting is defective.
X Visit a qualified specialist workshop.
b
Auto Lamp Function
Inoperative
The light sensor is defective.
X Visit a qualified specialist workshop.
b
Switch Off Lights
The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X Turn the light switch to Ã.
Engine
Display messagesPossible causes/consequences and M Solutions
+
Check Coolant
Level See OperaZ
tor'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 Add coolant, observing the warning notes before doing so
(Y page 303).
X If coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop.
?The fan motor is faulty. XAt coolant temperatures below 248 ‡ (120 †), drive to the
nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. drivin g in moun-
tainous terrain, and stop-and-go traffic.
246Display messages
On-board computer and displays

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 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.
iIn some states, you must immediately visit a qualified sp ecial-
ist workshop as soon as the yellow Check Engine warning lam p
lights up. This is due to the legal requirements in effect in these
states. If in doubt, check whether such legal regulations a pply in
the state in which you are currently driving.
8
The yellow reserve fuel
warning lamp flashes
while the vehicle is in
motion. In addition,
the ; Check Engine
warning lamp may light
up.The fuel system pressure is too low. The fuel filler cap i s not closed
correctly or the fuel system is leaking.
X Observe the additional display messages in the multifunction
display.
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.
8
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.
Warning and indicator lamps in the instrument cluster267
On-board computer and displays
Z

ProblemPossible causes/consequences and M Solutions
X
Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Check the coolant level and add coolant ( Y page 303). Observe
the warning notes.
X If you need to add coolant more often than usual, have the
engine coolant system checked.
X At coolant temperatures below 248 ‡ (120 †), drive to the
nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. drivin g in moun-
tainous terrain, and stop-and-go traffic.
Driving systems
ProblemPossible causes/consequences and M Solutions
·
The red distance warn-
ing lamp lights up while
the vehicle is in motion. A warning tone also
sounds.GWARNING
You are approaching a vehicle or a stationary obstacle in your line
of travel at too high a speed.
There is a risk of an accident.
X Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to
brake or take evasive action.
More information about DISTRONIC PLUS ( Y page 176) and
PRE

! 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.
XPull release lever : on the hood.
The hood is released.
X Reach into the gap, pull hood catch han-
dle ; up and lift the hood.
If you lift the hood by approximately 15 in
(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 your driving style, the vehicle
consumes up to 0.9 US qt (0.8 liters) of oil per
600 miles (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 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 dip-
stick
GWARNING
Certain components in the engine compart-
ment, 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.
Example: vehicles with a gasoline engine
Engine compartment301
Maintenance and care
Z

XTo open: pull out cover : slightly at the
bottom in the direction of arrow =.
X Pull cover : outwards in the direction of
arrow ; and remove it.
X To close: clip in cover : on the front of the
dashboard.
X Fold cover : inwards until it engages.
Fuse box in the engine compartment
GWARNING
When the hood is open and the windshield
wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windshield wipers and
the ignition before opening the hood.
! Make sure that no moisture can enter the
fuse box when the cover is open.
! When closing the cover, make sure that it
is lying correctly on the fuse box. Moisture
seeping in or dirt could otherwise impair
the operation of the fuses.
X Make sure that the windshield wipers are
turned off.
X Open the hood.
XUse a dry cloth to remove any moisture
from the fuse box.
X To open: take lines ; from the guides.
X Open clamps :.
X Remove the fuse box cover forwards.
X To close: check whether the rubber seal is
lying correctly in the cover.
X Insert the cover at the rear of the fuse box
into the retainer.
X Fold down cover and close clamps :.
X Secure lines ; in the guides.
X Close the hood.
Fuse box in the cargo compartment
!
Make sure that no moisture can enter the
fuse box when the cover is open.
! When closing the cover, make sure that it
is lying correctly on the fuse box. Moisture seeping in or dirt could otherwise impair
the operation of the fuses.
X Open the tailgate.
Fuses329
Roadside Assistance
Z