ECU MERCEDES-BENZ GLK SUV 2012 Service Manual

Problem Possible causes/consequences and
M
MSolutions 8
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning. 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. ?
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature 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.
X
Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 164).
X Consult a qualified specialist workshop. 292
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Useful information
i This Owner's Manual describes all mod-
els, series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos-
sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: (Y page 27). Loading guidelines
G
WARNING
Secure and position the load as described in
the loading guidelines.
Otherwise, vehicle occupants could
be injured by the load being thrown around in
the event of sharp braking, a sudden change
in direction or an accident.
You will find further information in the "Secur-
ing a load" section.
Even if you follow all the loading guidelines,
the load will increase the risk of injury in the
event of an accident. G
WARNING
Keep the tailgate closed when the engine is
running. Otherwise, you could be poisoned by
exhaust fumes entering the vehicle.
The handling characteristics of a laden vehi-
cle are dependent on the distribution of the
load within the vehicle. For this reason, you
should observe the following notes when
transporting a load:
R when transporting a load, never exceed the
maximum permissible gross vehicle weight
or the permissible axle loads for the vehicle
(including occupants).
R position heavy loads as far forwards as pos-
sible and as low down in the load compart-
ment as possible. R
the load must not protrude above the upper
edge of the seat backrests.
R always place the load against the rear or
front seat backrests. Make sure that the
seat backrests are securely locked into
place.
R hook in the safety net when loading.
R always place the load behind unoccupied
seats if possible.
R secure the load with sufficiently strong and
wear-resistant lashing material. Pad sharp
edges for protection.
i Load restraints are available at any quali-
fied specialist workshop, e.g. a Mercedes-
Benz Service Centre. Stowage areas
Stowage compartments
Important safety notes G
WARNING
The stowage compartments must be closed
when items are stored in them. Luggage nets
are not designed to secure heavy items of
luggage.
You or other vehicle occupants could be
injured by objects being thrown around if you:
R brake sharply
R change direction suddenly
R are involved in an accident
Sharp-edged and fragile objects must not be
placed in the luggage net.
Do not place hard objects in the map pockets.
Objects must not protrude from the map
pockets. 296
Stowage areasStowing and features

Stowage compartment under the front
seats G
WARNING
Only load the stowage compartment with the
maximum permissible load of 1.5 kg. Other-
wise, the transported load could, for example,
be thrown out of the stowage compartment if
you change direction suddenly or brake
sharply, and you or others could be injured. X
To open: pull handle :up and fold
cover ;forwards.
Rear stowage compartments Stowage compartment in the rear com-
partment
X
To open: fold down seat armrest ;.
X Fold cover :of the armrest upwards. Stowage net
G
WARNING
Only place lightweight objects in the luggage
net. Do not use it to transport heavy, sharp-
edged or fragile objects. The luggage net can-
not secure the objects sufficiently in the event
of an accident.
Stowage nets are located in the front-
passenger footwell and on the left-hand side
of the luggage compartment. Enlarging the luggage compartment
Important safety notes G
WARNING
Do not carry heavy or hard objects inside the
vehicle or in the luggage compartment unless
they are secured.
Otherwise, you and other vehicle occupants
could be injured by objects being thrown
around the vehicle in the event of sharp brak-
ing, a sudden change in direction or an acci-
dent.
When using the luggage compartment
enlargement, you should always clip in the
safety net, if at hand. G
WARNING
Always drive with the tailgate closed. Exhaust
fumes could otherwise enter the vehicle inte-
rior.
! Before folding the rear seat backrest for-
wards, make sure that the head restraints
are pushed in (lowest detent). Otherwise,
the front seats, the armrests and the Rear
Seat Entertainment System could be dam-
aged.
The left-hand and right-hand rear seat backr-
ests can be folded forwards separately to
increase the luggage compartment capacity. 298
Stowage areasStowing and features

Folding the rear seat backrest forward
X
Fully insert the backrest head restraints
(Y page 99).
X Move the driver's or front-passenger seat
forward if necessary.
X Pull left-hand or right-hand release han-
dle ;of the seat backrest forwards.
Corresponding seat backrest :is
released.
X Fold backrest :forwards.
X Move the driver's or front-passenger seat
back if necessary.
Folding the rear seat backrest back :
Backrest
; Lock verification indicator
= Backrest release handle
X Move the driver's or front-passenger seat
forward if necessary.
! Make sure that the seat belt does not
become trapped when folding the rear seat backrest back. Otherwise, it could be dam-
aged.
X Fold seat backrest :back until it engages.
Red lock status indicator ;is no longer
visible. G
WARNING
Make sure that the seat backrest is correctly
engaged. The red lock verification indicators
on the left and right sides should no longer be
visible. If they are visible, the backrests are
not locked in position.
Occupants could otherwise be injured in the
event of an accident, e.g. by objects being
thrown forwards through the vehicle interior
from the luggage compartment.
X Adjust the head restraints if necessary
(Y page 99).
X Move the driver's or front-passenger seat
back if necessary. Securing a load
Lashing eyelets G
WARNING
Use only the intended lashing eyelets; on no
account should you use the child-seat anchor-
age points on the rear seat backrest.
Distribute the load on the lashing eyelets
evenly.
Otherwise, vehicle occupants could be
injured by objects being thrown around if you:
R brake sharply
R change direction suddenly
R are involved in an accident
Please observe the loading guidelines.
Observe the following notes on securing
loads:
R secure the load using the lashing eyelets.
R do not use elastic straps or nets to secure
a load, as these are only intended as an
anti-slip protection for light loads. Stowage areas
299Stowing and featu res Z

R
do not route lashing materials across sharp
edges or corners.
R pad sharp edges for protection.
There are four lashing eyelets in the luggage
compartment and two in the rear-compart-
ment footwells. :
Lashing eyelets in the load compartment :
Lashing eyelets in the rear-compartment
footwell
Bag hook G
WARNING
Only hang light loads on the bag holders. Do
not use them to transport heavy, sharp-edged
or fragile objects. When braking sharply,
changing direction quickly or in the event of
an accident, the bag hooks will not secure the
items sufficiently. This could result in injury to
yourself or others.
! The bag hook can bear a maximum load
of 5 kg. Do not use it to secure a load.
There is one bag hook on the left side wall in
the luggage compartment and there are two hooks on the right and left of the lower D-pillar
trim.
Luggage compartment cover
Important safety notes G
WARNING
The luggage compartment cover is not a
restraint system. Secure the load under the
luggage compartment cover by suitable
means. Make sure that the luggage compart-
ment cover is engaged securely. If luggage is
not sufficiently secured, it can be thrown over
the backrest into the passenger compart-
ment, for instance during heavy braking, sud-
den changes of direction or in the event of an
accident. You could cause an accident or
cause injury to yourself and others.
! When loading the vehicle, make sure that
you do not stack the load in the luggage
compartment higher than the lower edge of
the side windows. Do not place heavy
objects on top of the luggage compartment
cover.
The luggage compartment cover is located
behind the rear bench seat backrest.
i You can fold up the solid section of the
luggage compartment cover approximately
45° to facilitate loading the luggage com-
partment. 300
Stowage areasStowing and features

Extending and retracting the luggage
compartment cover X
To extend: pull luggage compartment
cover :back and clip it into the retainers
on the left and right.
X To retract: unhook luggage compartment
cover :from the retainers on the left and
right and guide it forwards by the grab han-
dle until it is fully retracted.
Fitting/removing the luggage compart-
ment cover X
To remove: make sure that luggage com-
partment cover :is rolled up.
X Press handle ;on the right underside to
the left.
X Remove luggage compartment cover :.X
To fit: attach luggage compartment
cover :to the opening on the left-hand
side.
X Press handle ;to the left.
X Allow luggage compartment cover :to
engage in the appropriate recess. Safety net
Important safety notes G
WARNING
You must make sure that the safety net is
correctly secured at the top and bottom.
Do not use a damaged safety net.
The safety net cannot restrain heavy loads.
For this reason, you should always secure the
load.
Otherwise, objects that have not been
secured sufficiently might be thrown around
if you brake suddenly, change direction sud-
denly or are involved in an accident, and could
cause you an injury.
Preparing the safety net The safety net can be used in two different
positions (behind the B-pillar or the C-pillar).
R
The brackets behind B-pillar :are
required for the luggage compartment
enlargement . Stowage areas
301Stowing and features Z

X
Release hook =from the bracket on the
underside of the luggage compartment
floor. X
Engage hook =into rain trough ?.
i Stowage compartments Aand Bcan be
used to stow small, light and flat objects.
! Before you close the tailgate, unhook the
hook from the rain trough and fold the lug-
gage compartment floor down.
X To close: unhook hook =from rain
trough ?.
X Fasten hook =to the bracket on the
underside of the luggage compartment
floor.
X Fold the luggage compartment floor down.
X Press the luggage compartment floor down
until it engages. Roof carrier
Important safety notes G
WARNING
An incorrectly secured roof carrier, ski rack or
load could become detached from the vehi-
cle. These objects might then be thrown
around, and could injure you or others or
cause an accident. Follow the roof carrier/ski
rack manufacturer's installation instructions
and special instructions for use.
The roof load raises the vehicle's centre of
gravity, thereby affecting vehicle handling.
You must always observe the maximum roof
load of 75 kg. Always adapt your driving style
to the prevailing road, traffic and weather
conditions and drive with particular care if the
roof is laden.
! Mercedes-Benz recommends that you
only use roof carriers that have been tested
and approved for Mercedes-Benz vehicles.
This helps to prevent damage to the vehi-
cle.
Position the load on the roof carrier in such
a way that the vehicle will not sustain dam-
age even when it is in motion.
Ensure that, depending on the vehicle's
equipment, you can raise the panorama
sliding sunroof fully and open the tailgate
fully when the roof carrier is fitted.
Attaching the roof carrier X
Secure the roof carrier to the roof rails.
X Observe the manufacturer's installation
instructions. 304
Stowage areasStowing and fea
tures

i
When using a bracket connected to the
mobile phone via Bluetooth ®
and you wish
to proceed with a call:
Switch to private mode before removing
the key from the ignition lock. Otherwise, it
may take up to 20seconds before the
mobile phone disconnects from the sys-
tem. Only then can the telephone call con-
tinue.
Information on the necessary steps for set-
ting up "private mode" can be found in the
separate mobile phone operating instruc-
tions.
i Not all mobile phones support "private
mode".
Mobile telephone bracket in the stow-
age space You can fold the pre-installed bracket up to
improve access to the stowage space
beneath it. Depending on the vehicle's equip-
ment, a USB connection and an AUX-IN con-
nection/Media Interface are fitted in the
stowage compartment (Y page 297).X
To fold the bracket up: press button:.
X To fold the bracket down: press the
bracket down and allow it to engage. Floormat on the driver's side
G
WARNING
Make sure that there is sufficient clearance
around the pedals when floormats are used,
and that the floormats are properly secured.
The floormats must be correctly secured at all
times using the securing knob and retainers.
Before you drive off, check the floormats and
secure them if necessary. A floormat which is
not properly secured can slip and thereby
interfere with the movement of the pedals.
Do not place floormats on top of one another. X
Slide the seat backwards.
X To fit: lay the floormat in the footwell.
X Press studs :onto retainers ;.
X To remove: pull the floormat from retain-
ers ;.
X Remove the floormats. Retrofitted anti-glare film
Retrofitted anti-glare film on the inside of the
windows can interfere with radio/mobile
telephone reception. This is particularly the
case for conductive or metallic-coated films.
You can obtain information about anti-glare
film from a qualified specialist workshop. 310
FeaturesStowing and features

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

i
The vehicle should preferably be washed
by hand using a soft sponge, car shampoo
and plenty of water.
i Use only insect remover and car shampoo
from the range of recommended and
approved Mercedes-Benz care products.
Cleaning the windows G
WARNING
Switch off the windscreen wipers and remove
the key from the ignition lock before cleaning
the windscreen or the wiper blades. On vehi-
cles with KEYLESS-GO, press the Start/Stop
button repeatedly until all indicator lamps in
the instrument cluster have gone off. The
windscreen wipers could otherwise move and
injure you.
! Only fold the windscreen wipers away
from the windscreen when vertical. Other-
wise, you will damage the bonnet.
! Do not use dry cloths, abrasive products,
solvents or cleaning agents containing sol-
vents to clean the inside of the windows.
Do not touch the insides of the windows
with hard objects, e.g. an ice scraper or
ring. There is otherwise a risk of damaging
the windows.
! Clean the water drainage channels of the
windscreen and the rear window at regular
intervals. Deposits such as leaves, petals
and pollen may under certain circumstan-
ces prevent water from draining away. This
can lead to corrosion damage and damage
to electronic components.
X Clean the inside and outside of the win-
dows with a damp cloth and a cleaning
agent that is recommended and approved
by Mercedes-Benz.
Cleaning the wiper blades G
WARNING
Switch off the windscreen wipers and remove
the key from the ignition lock before cleaning the windscreen or the wiper blades. On vehi-
cles with KEYLESS-GO, press the Start/Stop
button repeatedly until all indicator lamps in
the instrument cluster have gone off. The
windscreen wipers could otherwise move and
injure you.
! Only fold the windscreen wipers away
from the windscreen when vertical. Other-
wise, you will damage the bonnet.
! Do not pull on the wiper blade. Otherwise,
the wiper blade could be damaged.
! Do not clean wiper blades too often and
do not rub them too hard. Otherwise, the
graphite coating could be damaged. This
could cause wiper noise.
! Hold the wiper arm securely when folding
back. The windscreen could be damaged if
the wiper arm hits against it suddenly.
X Fold the wiper arms away from the wind-
screen.
X Clean the wiper blades carefully using a
damp cloth.
X Fold the windscreen wipers back again
before switching on the ignition.
Cleaning the exterior lighting !
Only use cleaning agents or cleaning
cloths that are suitable for plastic lenses.
Unsuitable cleaning agents or cleaning
cloths could scratch or damage the plastic
lenses of the exterior lighting.
X Clean the plastic lenses of the exterior
lighting using a wet sponge and a mild
cleaning agent, e.g. Mercedes-Benz car
shampoo. Or clean the exterior lighting
with cleaning cloths.
Cleaning the mirror turn signal !
Only use cleaning agents or cleaning
cloths that are suitable for plastic lenses.
Unsuitable cleaning agents or cleaning 320
CareMaintenance and care