2015 MERCEDES-BENZ GLK-CLASS SUV check engine light

Problems with the seat heating
ProblemPossible causes/consequences and M Solutions
The seat heating has
switched off prema-
turely or cannot be
switched on.The on-board voltage is too low because too many elect rical con-
sumers are switched on.
X Switch off electrical consumers that you do not need, such as
the rear window defroster or interior lighting.
Steering wheel
Important safety notes
GWARNING
You could lose control of your vehicle if you do
the following while driving:
R adjust the driver's seat, head restraint,
steering wheel or mirrors
R fasten the seat belt
There is a risk of an accident.
Adjust the driver's seat, head restraint, steer-
ing wheel and mirror and fasten your seat belt before starting the engine.
GWARNING
If the steering wheel is unlocked while the
vehicle is in motion, it could change position
unexpectedly. This could cause you to lose
control of the vehicle. There is a risk of an
accident.
Before starting off, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion.
GWARNING
Children could injure themselves if they
adjust the steering wheel. There is a risk of
injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Neverleave children unsupervised in the vehicle.
The electrically adjustable steering wheel can
still be adjusted when there is no SmartKey in
the ignition lock.
Adjusting the steering wheel man-
ually
GWARNING
If the steering wheel is unlocked while the
vehicle is in motion, it could change position
unexpectedly. This could cause you to lose
control of the vehicle. There is a risk of an
accident.
Before starting off, make sure the steering
wheel is locked. Never unlock the steering
wheel while the vehicle is in motion.
:Release lever
;To adjust the steering wheel height
=To adjust the steering wheel position
(fore-and-aft adjustment)
X Push release lever : down completely.
The steering column is unlocked.
X Adjust the steering wheel to the desired
position.
X Push release lever : up completely.
The steering column is locked.
X Check if the steering column is locked.
When doing so, try to push the steering
106Steering wheel
Seats, steering wheel and mirrors

Problems with the windshield wipers
ProblemPossible causes/consequences and M Solutions
The windshield wipers
are jammed.Leaves or snow, for example, may be obstructing the windshield
wiper movement. The wiper motor has been deactivated. X
For safety reasons, you should remove the SmartKey from the
ignition lock.
or X Switch off the engine using the Start/Stop button and o pen the
driver's door.
X Remove the cause of the obstruction.
X Switch the windshield wipers back on.
The windshield wipers
fail completely.The windshield wiper drive is malfunctioning.
X Select another wiper speed on the combination switch.
X Have the windshield wipers checked at a qualified specialist
workshop.
The windshield washer
fluid from the spray
nozzles no longer hits
the center of the wind-
shield.The spray nozzles are misaligned.
X Have the spray nozzles adjusted at a qualified specialist work-
shop.
Windshield wipers129
Lights and windshield wipers
Z

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