2012 MERCEDES-BENZ G-Class automatic transmission

Problems with the automatic transmission
Problem Possible causes/consequences and
M Solutions
The acceleration ability
is deteriorating.
The transmission no
longer changes gear. The transmission is in emergency mode.
It is only possible to shift into
second
gear and reverse gear.
X Stop the vehicle.
X Shift the transmission to position P.
X Turn the SmartKey to position 0 in the ignition lock.
X Wait at least ten seconds before restarting the engine.
X Shift the transmission to position D or R.
If D
is

selected, the transmission shifts into second gear; if R is
selected, the transmission shifts into reverse gear.
X Have the transmission checked at a qualified specialist
workshop immediately. You hear a warning
tone. You have:
R
switched off the engine
R opened the driver's door
R not moved the selector lever to position P
X Move the selector lever to
P.
Releasing the parking lock manually
In the

event of a malfunction, it is possible to
release the selector lever lock manually to
move it out of position P, e.g. if you wish to
have the vehicle towed. X
Apply the parking brake.
X Insert a suitable implement :
into the
opening protected by the flap. X
Press implement : downwards and
simultaneously move

the selector lever out
of position P.
X Remove implement :.
The selector

lever can now be moved freely
until it is returned to position P.
i The protective

flap only closes completely
if you briefly press to selector lever towards
D-. Refueling
Important safety notes
G
WARNING
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious
personal injury.
Never allow sparks, flames or smoking
materials near gasoline. 124
Refueling
Driving and parking

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

For this reason, in the event of heavy rain or
in conditions in which hydroplaning can
occur, you must drive in the following
manner:
R
lower your speed.
R avoid ruts.
R brake carefully.
Driving on flooded roads !
Do not drive through flooded areas.
Check the
depth of any water before driving
through it. Drive slowly through standing
water. Otherwise, water may enter the
vehicle interior or the engine compartment.
This can damage the electronic
components in the engine or the automatic
transmission. Water can also be drawn in
by the engine's air suction nozzles and this
can cause engine damage.
If you have to drive on stretches of road on
which water has collected, please bear in
mind that:
R the maximum permissible still water depth
is 50 cm.
R you should drive no faster than at walking
pace.
Off-road fording :
Fording depth, 20 in (50 cm)
The fording depth must not exceed 20 in
(50 cm)

when the vehicle is loaded and ready
to drive. !
The water depth must not exceed 20 in
(50 cm). Note that the possible fording
depth is less in flowing water.
i You may only drive through freshwater.
R Observe the

safety notes (Y page 134) and
the general notes (Y page 135) on off-road
driving.
R Establish how deep the water is and the
characteristics of the body of water before
fording.
R Switch off the auxiliary heating and the air-
conditioning system.
R Shift the transfer case to
LOW (Y page 145).
R Engage the differential locks, if necessary
(Y page 148).
R Restrict the shift range to 1 or 2
(Y page 121).
R Avoid high engine speeds.
R Enter and exit the water at a flat place and
at a steady walking pace.
! Under no circumstances should you
accelerate before entering the water. The
bow wave could cause water to enter and
damage the engine and other assemblies.
R Drive slowly and at an even speed through
the water.
R Do not stop and do not switch off the
engine.
! Do not open any of the vehicle's doors
while fording. Otherwise, water could get
into the vehicle interior and damage the
vehicle's electronics and interior
equipment.
R Water offers a high degree of resistance,
and the ground is slippery and in some
cases unstable. Therefore, it is difficult and
dangerous to pull away in the water.
R Ensure that a bow wave does not form as
you drive.
R Clean any mud from the tire tread after
fording.
R Apply the brakes to dry them after fording. Driving tips
133
Driving and parking Z

R
Avoid high engine speeds. Drive at
appropriate engine speeds (maximum
3000 rpm).
R Do not shift the automatic transmission to
transmission position N.
R Always check the vehicle for damage after
off-road driving.
i Information about retrofitting special all-
terrain tires is available from any
authorized Mercedes-Benz Center. H
Environmental note
Protection of the environment is of primary
importance. Treat nature with respect.
Observe all prohibiting signs.
Checklist before driving off-road X
Engine oil level: check the engine oil level
and add oil if necessary.
Only then does the engine receive enough
oil when the vehicle is standing on a steep
incline.
! If the engine oil warning lamp lights up
while the vehicle is in motion, stop the
vehicle in

a safe place as soon as possible.
Check the engine oil level. The engine oil
warning lamp warning must not be ignored.
Continuing the journey while the symbol is
displayed could lead to engine damage.
X Wheel-changing tool kit: check that the
jack is

working and make sure you have the
lug wrench, a robust tow cable and a folding
spade in the vehicle.
X Wheels and tires: check the tire tread
depth and tire pressure.
X Check for damage and remove any foreign
objects, e.g. small stones, from the
wheels/tires.
X Replace any missing valve caps.
X Replace dented or damaged wheels.
X Carry a sound spare wheel. Checklist after driving off-road G
WARNING
If you notice sudden significant vibrations or
unusual handling performance or if you
suspect that damage has occurred to the
vehicle, you should activate the hazard
warning lamps, gently reduce speed and
carefully head for an area that is located at a
safe distance from the road.
Check the tires and the underside of the
vehicle for damage. If the vehicle seems
unsafe, have the vehicle towed away to the
nearest Mercedes-Benz Center or tire dealer
to be repaired.
Driving over rough terrain places greater
demands on your vehicle than driving on
normal roads. After driving off-road, check
the vehicle.

This allows you to detect damage
promptly and reduce the risk of an accident
to yourself and other road users.
X Shift the transfer case to HIGH
(Y page 145).
X Disengage the differential locks
(Y page 148).
X Clean the headlamps and rear lights and
check for damage.
X Clean the front and rear license plates.
X Clean the wheels and tires with a water jet
and remove any foreign objects.
X Clean the wheels, tires, wheel arches and
the vehicle underside with a water jet;
check for

any foreign objects and damage.
X Check whether twigs or other parts of
plants have become trapped. These
increase the risk of fire and can damage
fuel pipes, brake hoses or the rubber
bellows of the axle joints and propeller
shafts.
X After the trip, examine without fail the
entire undercarriage,

wheels, tires, brakes,
bodywork structure, steering, chassis and
exhaust system for damage. 136
Driving tips
Driving and parking

X
After driving for extended periods across
sand, mud,
gravel, water or in similarly dirty
conditions, have the brake discs, wheels,
brake pads/linings and axle joints checked
and cleaned.
X If you notice strong vibrations after off-road
driving, check for foreign objects in the
wheels and drive train and, if necessary,
remove them. Foreign objects can disturb
the balance and cause vibrations.
X Test the brakes.
Driving on sand G
WARNING
Do not reduce the tire inflation pressure
before driving through sand. However, if you
do so, remember to correct the tire inflation
pressure before continuing your trip. Driving
with reduced

tire inflation pressure increases
the risk of losing control of the vehicle and
rolling over.
Observe the following rules when driving on
sand:
R shift the transfer case to
LOW (Y page 145).
R avoid high engine speeds.
R limit the shift range of the automatic
transmission according to the off-road
conditions.
R drive quickly to overcome the rolling
resistance. Otherwise, the vehicle could dig
itself into the sand.
R drive in the tracks of other vehicles if
possible. Make sure that the ruts are not
too deep, that the sand is firm enough and
that your vehicle has sufficient ground
clearance.
Tire ruts and gravel roads Observe the following rules when driving
along
ruts

in off-road terrain or on roads with
loose gravel: !
Check that the ruts are not too deep and
that your vehicle has sufficient clearance.
Otherwise, your vehicle could be damaged
or bottom out and get stuck.
R shift the transfer case to
LOW (Y page 145).
R avoid high engine speeds.
R observe the

safety notes (Y page 134) and
the general notes (Y page 135) on off-road
driving.
R restrict the shift range of the automatic
transmission to 1 (Y page 121).
R drive slowly.
R where ruts are too deep, drive with the
wheels of one side on the center grassy
area, if possible.
Driving over obstacles !
Obstacles could damage the floor of the
vehicle or components of the chassis. Ask
passengers for

guidance when driving over
large obstacles. The passenger should
always keep a safe distance from the
vehicle when doing so in order to avoid
injury as a result of unexpected vehicle
movements. After driving off-road or over
obstacles, check the vehicle for possible
damage, especially to the underbody and
the components of the chassis.
Observe the following rules when driving over
tree stumps, large stones and other
obstacles: Driving tips
137
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

Shift ranges
H HIGH
Position for all normal on-road
driving conditions.
L LOW
Low-range position for driving off-
road.
Also for use on steep uphill or
downhill gradients, especially
when towing a trailer.
!
When the
transfer case is in the
off-road driving position LOW
range, the automatic
transmission does not shift up,
even when the engine has
reached the overrevving limit.
There is then a risk of engine
damage. Make sure that you do
not exceed the maximum
permissible engine speed.
The vehicle travels around half the
speed of on-road driving range
HIGH. The tractive power is
correspondingly higher. N Neutral
Neutral position.
No power is transmitted to the
drive wheels.
Shifting the transfer case
General information
G
WARNING
If you do not wait for the gear change process
to complete, it may not be correctly
implemented. The transfer case may then be
in neutral and the power transmission
between the engine and the drive axles may
be disengaged. The vehicle can then move
freely, even if a gear is engaged, and may
inadvertently start moving, particularly if it is
on a slope. There is therefore a risk of an
accident. Always wait for the gear change process from
HIGH to LOW and from LOW to HIGH to
complete. Do not turn off the engine while
changing
gear

and do not shift the automatic
transmission to another gear.
Observe the relevant messages in the
multifunction display. :
Current shift range
; Current transfer case position
Current shift range : and transfer case
position ; are shown in the instrument
cluster multifunction display.
The switch for the transfer case is on the
lower section of the center console. Transfer case switch
From HIGH to LOW
!
Only carry out the gear selection if:
R the engine is running.
R the vehicle is rolling.146
Off-road driving systems
Driving and parking