2012 MERCEDES-BENZ G-Class ignition

Problems with the fuel and fuel tank
Problem Possible causes/consequences and
M Solutions
Fuel is leaking from the
vehicle. G
Risk of explosion or fire
The fuel line or the fuel tank is defective.
X Turn the SmartKey to position
0 (Y
page
115) in the ignition lock
immediately and remove it.
X Do not restart the engine under any circumstances.
X Consult a qualified specialist workshop. The fuel filler flap
cannot be opened. The fuel filler flap is not unlocked.
or
The SmartKey batteries are discharged.
X
Unlock the vehicle (
Y page 60).
or
X Unlock the vehicle using the mechanical key ( Y page 61).
X Open the rear door.
X Manually unlock the fuel filler flap using the emergency release
(Y page 126). The fuel filler flap is unlocked, but the opening mechanism is
jammed.
X
Manually unlock the fuel filler flap using the emergency release
(Y page 126).
X Consult a qualified specialist workshop. Parking
Important safety notes
G
WARNING
Do not park this vehicle in areas where
combustible materials

can come into contact
with the hot exhaust system. Do not park the
vehicle on dry grassland or harvested grain
fields. Combustible materials, such as grass,
hay or leaves could be ignited by the hot
exhaust system and cause a vehicle fire. Unintended vehicle movement can cause
serious personal injury or damage to the
vehicle or the vehicle drivetrain. To reduce
such risks, always do the following before
turning
off

the engine and leaving the vehicle:
R keep your right foot on the brake pedal.
R engage the parking brake.
R shift the automatic transmission into park
position P.
R slowly release the brake pedal.
R when parked on an incline, always turn the
front wheels towards the road curb. Parking
127
Driving and parking
Z

R
turn the SmartKey in the ignition lock to
position 0 and remove the SmartKey from
the ignition lock.
R take the SmartKey with you and lock the
vehicle when leaving. Switching off the engine
G
WARNING
Do not turn off the engine before the vehicle
has come

to a complete stop. With the engine
not running, there is no power assistance for
the brake and steering systems. In this case,
it is important to keep in mind that a
considerably higher degree of effort is
necessary to brake and steer the vehicle. G
WARNING
Keep
in mind that turning off the engine alone
only will

shift the automatic transmission into
neutral position N automatically.
Always shift the automatic transmission 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.
X Shift the transmission to position P.
X Turn the SmartKey to position 0 in the
ignition lock and remove it.
The immobilizer is activated.
X Apply the parking brake firmly.
i The SmartKey

can only be removed if the
automatic transmission is in position P. Parking brake
G
WARNING
Engaging the parking brake while the vehicle
is in

motion can cause the rear wheels to 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. G
WARNING
When leaving the vehicle, always remove the
SmartKey from

the starter switch, take it with
you, and lock the vehicle. Do not leave
children unattended in the vehicle, or with
access to an unlocked vehicle. Children could
release the parking brake and/or shift the
automatic transmission out of park position
P, either of which could result in an accident
and/or serious personal injury. X
To apply: pull parking brake ;
up firmly.
When the

engine is running, the $ (USA
only) or J (Canada only) indicator lamp
lights up in the instrument cluster.
X To release: depress the brake pedal and
keep it depressed.
The selector lever lock is released.
X Pull parking brake ; up firmly.
X Press release button : on parking
brake ;
and

move the parking brake down
to the stop.
When the ignition is switched on or the
engine is running, the $ (USA only) or
J (Canada only) indicator lamp goes out
in the instrument cluster. Parking the vehicle for a long period
If you

leave the vehicle parked for longer than
four weeks, the battery may be damaged by
exhaustive discharge. 128
Parking
Driving and parking

Wet roads
G
WARNING
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. G
WARNING
Make sure that you do not endanger other
road users when you apply the brakes.
Limited braking performance on salt-
treated roads G
WARNING
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. Servicing the brakes G
WARNING
If brake pads or brake fluid other than those
recommended are 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. G
WARNING
Make sure that you do not endanger other
road users when you apply the brakes.
! If the

brake warning lamp lights up in the
instrument cluster and you hear a warning
tone even though the parking brake has
been released, 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. Have this work carried out at
an authorized Mercedes-Benz Center.
! A function or performance test should
only be carried out on a 2-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, you could damage the drive
train or the brake system.
! As the ESP ®
system operates
automatically, the engine and the ignition
must be switched off (the SmartKey must
be in position 0 or 1 in the ignition lock) if
the parking brake is tested on a brake
dynamometer (for a maximum of ten
seconds).
Braking applications triggered
automatically by ESP ®
may otherwise
seriously damage the brake system.
All checks and maintenance work on the
brake system must be carried out at a
qualified specialist workshop. Driving tips
131
Driving and parking Z

of the vehicle could cause an accident and/
or serious injury to you and others.
X Press the cruise control lever up : for a
higher speed

or down ; for a lower speed.
X Keep the cruise control lever pressed until
the desired speed is reached.
X Release the cruise control lever.
The new speed is stored.
i Cruise control is not deactivated if you
depress the accelerator pedal. For
example, if you accelerate briefly to
overtake, cruise control adjusts the
vehicle's speed to the last speed stored
after you have finished overtaking.
Making adjustments in 1 mph

(Canada:
1 km/h) increments X
Briefly press the cruise control lever
up :
for a higher speed or down
; for a
lower speed.
The last speed stored is increased or
reduced.
Deactivating cruise control There are several ways to deactivate cruise
control:
X
Briefly press the cruise control lever
forwards = .
or
X Brake.
Cruise control is automatically deactivated if:
R you apply the parking brake.
R you are driving below 20 mph (30 km/h

).
R ESP ®
intervenes or you deactivate ESP ®
.
R you shift the transmission to position N
while driving.
i The last speed stored is cleared when you
switch off the engine. 4MATIC
(permanent four-wheel drive)
4MATIC ensures that all four wheels are
permanently driven. Together with ESP ®
and
4ETS, it

improves the traction of your vehicle
whenever a drive wheel spins due to
insufficient grip. G
WARNING
If
a drive wheel is spinning due to insufficient
traction:
R While driving off, apply as little throttle as
possible.
R While driving, ease up on the accelerator
pedal.
R Adapt your speed and driving style to the
prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid.
4MATIC cannot prevent accidents resulting
from excessive speed.
! Never tow the vehicle with one axle
raised. This

may damage the transfer case.
Damage of this sort is not covered by the
Mercedes-Benz Limited Warranty. All
wheels must remain either on the ground
or be fully raised. Observe the instructions
for towing the vehicle with all wheels in full
contact with the ground.
i In wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if
you use winter tires (M+S tires), with snow
chains if necessary.
! When testing the parking brake, operate
the vehicle only briefly (for a maximum of
ten seconds) on a brake test dynamometer.
When doing this, turn the SmartKey to
position 0 or 1 in the ignition. Failure to do
this can cause damage to the drive train or
the brake system.
! Function or performance tests may only
be performed on a 2-axle dynamometer. If
you wish to operate the vehicle on such a
dynamometer, please consult an
authorized Mercedes-Benz Center Driving systems
141
Driving and parking Z

beforehand. You could otherwise damage
the drive train or the brake system.
Information about driving off-road
(Y page 134). Ultrasonic backing-up aid
Important safety notes G
WARNING
The ultrasonic backing up aid is only designed
to assist
you and may not detect all obstacles.
It is not a substitute for paying attention.
You are always responsible for safety and
must continue to pay attention to your
immediate surroundings when parking and
maneuvering. Otherwise, you could endanger
yourself and others. G
WARNING
Make sure that no persons or animals are in
the maneuvering range. Otherwise, they
could be injured.
The ultrasonic

backing up aid is an electronic
parking aid. It indicates visually and audibly
the distance between the rear area of your
vehicle and an object.
The ultrasonic backing up aid is activated
automatically when you switch on the ignition
and engage reverse gear.
The ultrasonic backing up aid monitors the
rear area of your vehicle using four sensors in
the rear bumper. :
Sensors in the rear bumper Range of the sensors The sensors must be free of dirt, ice and
slush; otherwise they may not function
correctly.
Clean

the sensors regularly, taking
care not to scratch or damage them
(Y page 220). Side view
Top view
Sensors
Center Approx. 59 in (approx.
150 cm)
Corners Approximately 40 in
(approximately 100 cm)
!
When parking,

pay particular attention to
objects above or below the sensors, such
as flower pots or trailer towbars. The
ultrasonic backing up aid does not detect
such objects when they are in the
immediate vicinity of the vehicle. You could
damage the vehicle or the objects.
Ultrasonic sources such as an automatic
car wash, the compressed air-brakes on a 142
Driving systems
Driving and parking

Problems with the ultrasonic backing-up aid
Problem Possible causes/consequences and
M SolutionsYou hear a warning
signal when backing
up. The ultrasonic backing up aid sensors are dirty or there is
interference.
X
Clean the ultrasonic backing up aid sensors ( Y page 220).
X Switch the ignition back on. The problem may be caused by an external source of radio or
ultrasound waves. The ultrasonic backing up aid is switched off.
X
See if the ultrasonic backing up aid functions in a different
location. You hear a warning
tone when backing up
or you do not hear a
warning tone and none
of the segments light
up. The ultrasonic backing up aid has malfunctioned and has switched
itself off.
X
Have the ultrasonic backing up aid checked at a qualified
specialist workshop as soon as possible. Rear view camera
Important safety notes The rear view camera is an optical parking aid.
It shows the area behind your vehicle in the
COMAND display.
G
WARNING
Make sure that no persons or animals are in
the maneuvering range. Otherwise, they
could be injured.
The rear view camera is in the tailgate above
the rear window wiper. :
Rear view camera
View through the camera The area behind the vehicle is displayed in a
mirror-inverted manner, as in the rear-view
mirror.
G
WARNING
The rear view camera is only an aid and may
show a distorted view of obstacles, show
them incorrectly or not at all. The rear view
camera is not a substitute for paying
attention. The
camera cannot show objects in
the following areas: 144
Driving systems
Driving and parking

R
very close to the rear bumper
R under the rear bumper
R under the spare wheel
R behind and close to the spare wheel
You are always responsible for safety and
must continue to pay attention to your
immediate surroundings when parking and
maneuvering. This applies to the areas
behind, in front of and beside the vehicle.
Otherwise, you could endanger yourself and
others. G
WARNING
Under the following circumstances, the rear
view camera
will not function, or will function
in a limited manner:
R the tailgate is open
R in heavy rain, snow or fog
R at night or in very dark places
R if the camera is exposed to very bright light
R if the area is lit by fluorescent light or LED
lighting (the display may flicker)
R if there is a sudden change in temperature,
e.g. when driving into a heated garage in
winter
R if the camera lens is dirty or obstructed
R if the rear of your vehicle is damaged. In this
event, have the camera position and setting
checked at a qualified specialist workshop.
Do not use the rear view camera in these
types of situation. You could otherwise injure
others or damage objects and your vehicle
while you are parking.
Activating the rear view camera X
Make
sure that the SmartKey is in position
2 in the ignition lock.
X Make sure that the "rear view camera"
function is selected in COMAND (see the separate operating instructions for
COMAND).
X Engage reverse gear.
The area

behind the vehicle is shown in the
COMAND display. Off-road driving systems
Transfer case
General information The vehicle has permanent all-wheel drive.
Power is always transmitted to both axles.
For further information on driving off-road,
see (
Y
page 134). Off-road driving systems
145
Driving and parking Z

R
the automatic transmission is in selector
lever position N.
R you are driving no faster than 25 mph
(40 km/h).
You could otherwise damage the transfer
case.
X Push the transfer case switch to LOW.
When the shift procedure is complete, the
L transfer case position appears in the
multifunction display.
X Shift the transmission to position D.
From LOW to HIGH
! Only carry out the gear selection if:
R the engine is running.
R the vehicle is rolling.
R the automatic

transmission is in selector
lever position N.
R you are driving no faster than 43 mph
(70 km/h).
You could otherwise damage the transfer
case.
X Push the transfer case switch to HIGH.
When the shift procedure is complete, the
H transfer case position appears in the
multifunction display.
If the gear change is not completed, the
following messages could appear in the
display:
R TC shift conditions not fulfilled
You have not met one or more shift
conditions.
R TC in neutral
The transfer case has canceled the gear
change process and is in N. The N transfer
case position appears in the multifunction
display. G
WARNING
If the transfer case is in Neutral, the park
position P of the automatic transmission will not hold the vehicle. The parking brake must
be engaged to hold the vehicle in place.
R TC shift procedure canceled
The transfer case has not performed the
gear change process.
X Carry out the gear change process again.
Make sure to meet all conditions for
changing gears.
R Transfer case Consult workshop
There is

a malfunction in the transfer case.
X Do not shift the transfer case.
X Have the vehicle checked as soon as
possible at

a qualified specialist workshop.
Shifting to neutral G
WARNING
If the transfer case is in Neutral, the park
position P of the automatic transmission will
not hold the vehicle. The parking brake must
be engaged to hold the vehicle in place.
X Turn the SmartKey to position 2 in the
ignition lock.
X Apply the parking brake.
X Depress the brake pedal.
X Move the selector lever to
position N (Y page 120).
X Push the transfer case switch to LOW for
about 30 seconds.
When the shift procedure is complete, the
N transfer case position appears in the
multifunction display.
i If the transfer case is in N, the SmartKey
is in the ignition lock and you open the
driver's door,

the TC in neutral message
appears in the multifunction display. If you
then release the parking brake, a warning
tone will sound. Off-road driving systems
147
Driving and parking Z