ECU MERCEDES-BENZ GLK SUV 2012 Workshop Manual

R
the emergency spare wheel
R the wheel bolts for the emergency spare
wheel
R the tyre inflation compressor
R the wheel wrench
R the folding wheel chock
R the jack
R the ratchet ring spanner
X Secure the vehicle to prevent it from rolling
away.
Securing the vehicle against rolling
away If your vehicle is equipped with a wheel chock,
it can be found in the vehicle tool kit
(Y page 327).
The folding wheel chock is an additional
securing measure to prevent the vehicle from
rolling away, for example when changing a
wheel. X
Fold both plates upwards :.
X Fold out lower plate ;.
X Guide the lugs on the lower plate fully into
the openings in base plate =. Securing the vehicle on level ground
X
On level ground: place wheel chocks or
other suitable items under the front and
rear of the wheel that is diagonally opposite
the wheel you wish to change. Securing the vehicle on slight downhill gradients
X
On downhill gradients: place wheel
chocks or other suitable items in front of
the wheels of the front and rear axle.
Raising the vehicle G
WARNING
If you do not position the jack correctly at the
appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle. Flat tyre
333Breakdown assistance Z

The following must be observed when raising
the vehicle:
R to raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If the jack is
used incorrectly, it could tip over while the
vehicle is raised.
R the jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suited for per-
forming maintenance work under the vehi-
cle.
R avoid changing the wheel on uphill and
downhill slopes.
R before raising the vehicle, secure it from
rolling away by applying the parking brake
and inserting wheel chocks. Never disen-
gage the parking brake while the vehicle is
raised.
R the jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, load-bearing underlay must be used.
On a slippery surface, a non-slip underlay
must be used, e.g. rubber mats.
R do not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacity due to the restricted
height.
R make sure that the distance between the
underside of the tyres and the ground does
not exceed 3 cm.
R never place your hands or feet under the
raised vehicle.
R never lie under the raised vehicle.
R never start the engine when the vehicle is
raised.
R never open or close a door or the tailgate
when the vehicle is raised.
R make sure that no persons are present in
the vehicle when the vehicle is raised. X
Using wheel wrench :, loosen the bolts on
the wheel you wish to change by about one
full turn. Do not unscrew the bolts com-
pletely.
The jacking points are located just behind the
front wheel arches and just in front of the rear
wheel arches (arrows). X
Take the ratchet ring spanner out of the
vehicle tool kit and place it on the hexagon
nut of the jack so that the letters AUFare
visible. 334
Flat tyreBreakdown assistance

!
You should have all work involving the
battery carried out at a qualified specialist
workshop. In the exceptional case that it is
necessary for you to disconnect the battery
yourself, make sure that:
R you switch off the engine and remove the
key. On vehicles with KEYLESS-GO,
ensure that the ignition is switched off.
Check that all the indicator lamps in the
instrument cluster are off. Otherwise,
electronic components, such as the
alternator, may be damaged.
R you first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic sys-
tem may be damaged.
R in vehicles with automatic transmission,
the transmission is locked in position P
after disconnecting the battery. The vehi-
cle is secured against rolling away. You
can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be fitted securely dur-
ing operation.
In order for the battery to achieve the maxi-
mum possible service life, it must always be
sufficiently charged.
Have the battery charge checked more fre-
quently if you use the vehicle mainly for short
trips or if you leave it standing idle for a
lengthy period. Consult a qualified specialist
workshop if you wish to leave your vehicle
parked up for a long period of time.
Like other batteries, the vehicle battery may
discharge over time if you do not use the
vehicle. In such cases, have the battery dis-
connected at a qualified specialist workshop.
You can also charge the battery with a
charger recommended by Mercedes-Benz.
For more information, please contact a quali-
fied specialist workshop.
i When you park the vehicle, remove the
key if you do not require any electrical con-
sumers. The vehicle will then use very little
energy, thus conserving battery power. i
If the power supply has been interrupted,
e.g. if the battery was discharged, you will
have to:
R set the clock; see the separate operating
instructions.
For vehicles with Audio 20 and a 4-button
multifunction steering wheel, see "Date/
Time" (Y page 227).
R reset the panorama sliding sunroof
(Y page 93).
R reset the function for automatically fold-
ing the exterior mirrors in/out by folding
the mirrors out once (Y page 104). Charging the battery
G
WARNING
Only charge the battery in a well-ventilated
area. As the battery is being charged, gases
can escape and generate minor explosions.
This could injure you and other persons or
cause damage to the paintwork or acid cor-
rosion on the vehicle.
You can obtain information on battery charg-
ers which allow the battery to be charged
while still installed from a qualified specialist
workshop. G
WARNING
There is a risk of acid burns during the charg-
ing process due to the gases which escape
from the battery. Do not lean over the battery
during the charging process. G
WARNING
Battery acid is caustic. Avoid contact with the
skin, eyes or clothing.
! Only charge the installed battery with a
battery charger which has been tested and
approved by Mercedes-Benz. These battery
chargers allow the battery to be charged
while still installed in the vehicle.
! Only use battery chargers with a maxi-
mum charging voltage of 14.8 V. Battery (vehicle)
339Breakdown assistance Z

R
the engine is not running.
R there is a brake system malfunction.
R there is a malfunction in the power supply
or the vehicle's electrical system.
The power assistance for the steering and the
brake force booster do not work when the
engine is not running. You will need more
force to steer and brake, you may have to
depress the brake pedal with maximum force.
Before towing away, make sure that the steer-
ing can be moved and is not locked.
If you tow or tow-start another vehicle, its
weight must not exceed the maximum per-
missible gross vehicle weight of your vehicle. G
WARNING
The vehicle is braked when the HOLD function
or DISTRONIC PLUS is activated. Therefore,
deactivate HOLD and DISTRONIC PLUS if the
vehicle is to be towed.
It is better to have the vehicle transported
than to have it towed.
! You may tow the vehicle for a maximum
of 50km. A towing speed of 50 km/h must
not be exceeded.
For towing distances over 50 km, the entire
vehicle must be lifted up and transported.
! Only secure the tow rope or towing bar to
the towing eyes. The vehicle may otherwise
be damaged.
! Do not use the towing eye for recovery,
as this could damage the vehicle. If in
doubt, recover the vehicle with a crane.
! Pull away smoothly when towing away or
tow-starting a vehicle. If the tractive power
is too high, the vehicles could be damaged.
! On vehicles with KEYLESS-GO, use the
key instead of the Start/Stop button. Turn
the key to position 2in the ignition lock and
shift the automatic transmission to N.
Then, turn the key back to 0and leave it in
the ignition lock. When towing a vehicle with an automatic
transmission, the transmission must be in
position
N.
The battery must be connected and charged.
Otherwise, you:
R cannot turn the key in the ignition lock to
position 2
R cannot shift the transmission to position
N on vehicles with automatic transmission
i Deactivate the automatic locking feature
(Y page 83). You could otherwise be locked
out when pushing or towing the vehicle.
Deactivate tow-away protection
(Y page 72) before the vehicle is towed. Fitting/removing the towing eye
Fitting the towing eye Vehicles with a trailer tow hitch: if you intend
to use the vehicle for towing, fit the ball cou-
pling (Y
page 217) and connect the towbar to
it.
X Remove the towing eye from the vehicle
tool kit ( Ypage 327). G
WARNING
The exhaust tail pipe may be hot. You could
burn yourself if you touch the tail pipe. Be
particularly careful when removing the rear
cover.
The mountings for the removable towing eyes
are located in the bumpers. They are at the
front and at the rear, under the covers. Towing and tow-starting
343Breakdown assistance Z

X
Release the brake pedal.
X Release the parking brake. Transporting the vehicle
The towing eyes or trailer tow hitch can be
used to pull the vehicle onto a trailer or trans-
porter if you wish to transport it.
X Vehicles with manual transmission:
shift to neutral.
X Vehicles with automatic transmission:
turn the key to position 2in the ignition
lock.
X Shift the automatic transmission to posi-
tion N.
As soon as the vehicle is loaded:
X Prevent the vehicle from rolling away by
applying the parking brake.
X Vehicles with manual transmission:
engage first or reverse gear.
X Vehicles with automatic transmission:
shift the automatic transmission to posi-
tion P.
X Turn the key in the ignition lock to position
0 and remove the key from the ignition
lock.
X Secure the vehicle.
! Only lash the vehicle down by the wheels
or wheel rims, not by parts of the vehicle
such as axle or steering components. Oth-
erwise, the vehicle could be damaged. Notes for 4MATIC vehicles
! Vehicles with 4MATIC must not be towed
with the front or rear axle raised; otherwise,
the transmission may be damaged.
If the vehicle has transmission damage or
damage to the front or rear axle, have it trans-
ported on a transporter or trailer.
In the event of damage to the electrical
system If the battery is defective, the automatic
transmission will be locked in position
P. To
shift the automatic transmission to position
N, you must provide power to the vehicle's
electrical system in the same way as when
jump-starting (Y page 341).
Have the vehicle transported on a transporter
or trailer. Recovering a vehicle that has become
stuck
! When recovering a trapped vehicle, do not
jerk the vehicle or pull it at an angle. If the
tractive power is too high, the vehicles
could be damaged.
If the drive wheels get trapped on loose or
muddy ground, recover the vehicle with the
utmost care, especially so if the vehicle is
laden.
Never attempt to recover a vehicle with a
trailer attached.
Pull out the vehicle backwards, if possible,
using the tracks it made when it became
stuck. Tow-starting (emergency engine
starting)
When tow-starting, it is important that you
observe the safety instructions (Y page 342)
and the legal requirements for the relevant
countries.
! Vehicles with automatic transmission
must not be tow-started. The transmission
may otherwise be damaged.
You can find information on "Jump-starting"
at (Y page 341).
Before tow-starting the following conditions
must be fulfilled:
R the battery is connected.
R the engine has cooled down.
R the exhaust system has cooled down. Towing and tow-starting
345Breakdown assistance Z

X
Switch on the hazard warning lamps
(Y page 114).
X Fit the towing eye (Y page 343).
X Secure the rigid towing bar or the towing
rope.
X Depress and hold the brake pedal.
X Turn the key to position 2in the ignition
lock.
X Depress the clutch pedal and keep it
depressed.
X Engage neutral.
X Release the brake pedal.
X Tow-start the vehicle.
X Engage second gear.
X Release the clutch pedal slowly; do not
depress the accelerator pedal while doing
so.
The engine is started.
X Depress the clutch pedal and shift to neu-
tral.
X Stop at a suitable place.
X Depress the parking brake.
X Remove the rigid towing bar or towing rope.
X Remove the towing eye (Y page 344).
X Switch off the hazard warning lamps. Electrical fuses
Important safety notes
G
WARNING
Only use fuses that have been approved for
Mercedes-Benz vehicles and which have the
correct fuse rating for the systems con-
cerned. Do not attempt to repair or bridge
faulty fuses. Using fuses which have not been
approved or attempting to repair or bridge
faulty fuses could cause the fuse to be over-
loaded and result in a fire. Have the cause
traced and rectified at a qualified specialist
workshop.
! Only use fuses that have been approved
for Mercedes-Benz vehicles and which have the correct fuse rating for the system
concerned. Otherwise, components or sys-
tems could be damaged.
The fuses in your vehicle serve to disconnect
faulty circuits. If a fuse blows, all the compo-
nents on the circuit and their functions will
fail.
Blown fuses must be replaced with fuses of
the same rating, which you can recognise by
the colour and fuse rating. The fuse ratings
are listed in the fuse allocation chart.
If the newly inserted fuse also blows, have the
cause traced and rectified at a qualified spe-
cialist workshop, e.g. a Mercedes-Benz
Service Centre. Before replacing a fuse
X Secure the vehicle against rolling away
(Y page 164).
X Switch off all electrical consumers.
X Turn the key to position 0in the ignition
lock and remove it (Y page 147).
or
X On vehicles with KEYLESS-GO, make sure
the ignition is switched off (Y page 147).
All indicator lamps in the instrument cluster
must be off.
The fuses are located in various fuse boxes:
R fuse box on the driver's side of the dash-
board
R fuse box in the engine compartment on the
left-hand side of the vehicle, when viewed
in the direction of travel
R fuse box in the stowage well under the lug-
gage compartment floor on the right-hand
side of the vehicle, when viewed in the
direction of travel
The fuse allocation chart is located in the
vehicle tool kit in the stowage compartment
under the luggage compartment floor
(Y page 327). 346
Electrical fusesBreakdown assistance

Dashboard fuse box
! Do not use a pointed object such as a
screwdriver to open the cover in the dash-
board. You could damage the dashboard or
the cover.
! 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
To 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
G
WARNING
Make sure that the windscreen wipers are
turned off and the key is pulled out of the igni-
tion lock before you open the cover of the fuse
box. Otherwise, the windscreen wipers and
the wiper rods above the cover could be set
in motion. This could lead to you or others
being injured by the wiper rods.
! 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 windscreen wipers are
switched off.
X Open the bonnet. X
Remove any existing moisture from the
fuse box using a dry cloth.
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 bonnet. Fuse box in the luggage 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. Elect
rical fuses
347Breakdown assis tance Z