2007 MERCEDES-BENZ G55AMG check engine

169 Controls in detail
Automatic transmission
Canceling gear range limit
Press and hold the gear selector lever
in the D+direction until
Dreappears in
the multifunction display (
page 164).
The transmission will shift from the
current gear range directly to gear
rangeD.
Shifting into optimal gear range
Press and hold the gear selector lever
in the D-direction.
The transmission will automatically
select the gear range suited for optimal
acceleration and deceleration. This will
involve shifting down one or more
gears.Emergency operation
(Limp-Home Mode)
If vehicle acceleration becomes less
responsive or sluggish or the transmission
no longer shifts, the transmission is most
likely operating in limp-home (emergency
operation) mode. In this mode only second
gear and reverse gear can be selected.
Stop the vehicle in a safe location.
Move the gear selector lever to park
positionP.
Turn off the engine.
Wait at least 10 seconds before
restarting.
Restart the engine.
Move the gear selector lever to
positionD (for second gear) or
positionR.
Have the transmission checked at an
authorized Mercedes-Benz Light Truck
Center as soon as possible.

190 Controls in detail
Climate control
Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condition-
ing.
Press button9 (page 183) once
more.
The indicator lamp on the button
comes on.
The air conditioning uses the refrigerant
R134a. This refrigerant is free of CFCs
which are harmful to the ozone layer.
Residual heat and ventilation
With the engine switched off, it is possible
to continue to heat or ventilate the interior
for up to 30 minutes. This feature makes
use of the residual heat produced by the
engine.Activating
Turn the SmartKey in the starter switch
to position0 or1 (
page 39).
or
Remove the SmartKey from the starter
switch.
Press button9 (page 183).
The indicator lamp on the button
comes on.
Deactivating
Press button9 (page 183) once
more.
The indicator lamp on the button goes
out.!If the air conditioning cannot be turned on
again, this indicates that the air conditioning is
losing refrigerant. The compressor has turned
itself off.
Have the air conditioning checked at the nearest
authorized Mercedes-Benz Light Truck Center.
iHow long the system will provide heating
depends on

the coolant temperature

the battery voltage
Regardless of the temperature and air volume
set on the climate control panel, an interior
temperature is aimed at by 72°F (22°C) and the
blower runs on low speed to protect the vehicle
battery.
iThe residual heat is automatically turned off:

when the ignition is switched on

after about 30 minutes

if the coolant temperature is too low

if the battery voltage drops

247 Operation
Driving instructions
Refer to the description of the Brake Assist
System (BAS) (
page 90).
Brake pad wear or a leak in the system may
be the reason for low brake fluid in the
reservoir.
The brake fluid level in the reservoir may
be too low if the brake warning lamp in the
instrument cluster comes on although the
parking brake is released (
page 326).
Observe additional messages in the
multifunction display that may appear
(
page 338).
Have the brake system inspected
immediately. Contact an authorized
Mercedes-Benz Light Truck Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact an authorized
Mercedes-Benz Light Truck Center.
Only install brake pads and brake fluid
recommended by Mercedes-Benz.After hard braking, it is advisable to drive
on for some time, rather than immediately
park, so the air stream will cool down the
brakes faster.
Driving off
Apply the brakes to test them briefly after
driving off. Perform this procedure only
when the road is clear of other traffic.
Warm up the engine smoothly. Do not
place full load on the engine until the
operating temperature has been reached.
To ensure sufficient traction during
off-road driving, activate differential locks
as needed (
page 175).
Warning!G
If other than recommended brake pads are
installed, or other than recommended brake
fluid is 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.
!When driving down long and steep grades,
relieve the load on the brakes by shifting into a
lower gear to use the engine’s braking power.
This helps prevent overheating of the brakes and
reduces brake pad wear.
!When driving off on a slippery surface, do
not allow a drive wheel to spin for an extended
period with the ESP
® switched off. Doing so may
cause serious damage to the drivetrain which is
not covered by the Mercedes-Benz Limited
Warranty.
!Simultaneously depressing the accelerator
pedal and applying the brake reduces engine
performance and causes premature brake and
drivetrain wear.

254 Operation
Driving instructions
Checklist before off-road driving
Engine oil level

Check the engine oil level with the
control system (
page 270). The
message
Engine oil level OK must
appear in the multifunction display.
Only then can the vehicle obtain a
trouble-free oil supply, even on steep
gradients.
!Observe the following during off-road
driving:

Keep doors, tailgate, windows, and
tilt/sliding sunroof closed.

Switch cruise control off.

Adjust vehicle speed to condition of terrain.
The more uneven, rutty, and steeper the
terrain, the lower the speed should be. Drive
through water slowly at an even speed,
avoiding a bow wave.

Be especially careful when driving in
unknown territory. It may be necessary to
get out of the vehicle and scout the path you
intend to take.

Watch out for obstacles, such as rocks,
holes, tree stumps, and ruts.

Avoid excessive engine speeds – drive at
moderate engine speeds (max. 3 000 rpm).

Before driving through water, determine its
depth.

Do not stop vehicle while immersed in water,
and do not shut off the engine.

In sandy soil, drive at a steady speed as
allowed by conditions. This helps overcome
the vehicle rolling resistance and reduces
the likelihood of the vehicle sinking into the
ground.

Do not initiate jumps with the vehicle. It
interrupts the forward momentum of the
vehicle.

Always drive on slopes with the engine
running and the vehicle in gear.

Inspect the vehicle for possible damage after
each off-road trip.
Warning!G
Do not reduce the tire inflation pressure
before driving through sand. However, if you
do so, remember to correct the tire inflation
pressure (
page 288) before continuing
your trip. Driving with reduced tire inflation
pressure increases the risk of losing control
of the vehicle and rolling over.
!If a engine oil level warning message
(
page 351) appears in the multifunction
display while driving, stop the vehicle in a safe
location or as soon at is safe to do so. Check the
engine oil level (
page 270).
The engine oil level warning messages should
not be ignored. Extended driving with the
message displayed could result in serious engine
damage that is not covered by the
Mercedes-Benz Limited Warranty.

256 Operation
Driving instructions

Driving on embankments, slopes and
other steep inclines should only be
done straight uphill or downhill, i.e. in
the line of gravity. Maximum vehicle
climbing ability is a 80% grade which is
equivalent to a slope angle of approxi-
mately 38 degrees. Keep in mind that
the climbing ability of the vehicle
depends on terrain conditions.

Select gear range2 or1 on the auto-
matic transmission (
page 167).

Drive slowly.

Utilize the engine’s braking power
when descending a slope, observe the
engine speed (do not overrev the
engine). Apply the service brake as
needed.

Check the brakes after a lengthy
downgrade drive.Traction in steep terrain
Be easy on the accelerator and watch for
continuous wheel traction when driving
uphill.
iFor maximum engine speed, see “Instru-
ment cluster” (
page 26) and see “Engine”
(
page 415).
Warning!G
Never turn the vehicle around on steep
inclines. The vehicle might roll over. If the
vehicle cannot complete the attempted
climb, back it down in reverse gear.
iThe 4-ETS helps greatly when starting out on
a steep incline when the front wheels have then
the tendency to slip due to the weight shifting
away from the front axle.
The 4-ETS recognizes the situation and limits the
torque for the front wheels by braking them.
Simultaneously the torque for the rear wheels is
provided.

258 Operation
Driving instructions

Comply with the warnings
(
page 253) and rules for off-road
driving (
page 253).

Switch off the exterior lamps as well as
the climate control.

Select gear range2 or1 on the auto-
matic transmission (
page 167).

Enter and leave the water only at a
shallow spot, driving at walking speed.

Drive through the water slowly and at a
constant speed.

Do not stop vehicle while immersed in
water, and do not shut off the engine.
There is a very high level of driving
resistance in water. The surface is
slippery and may not be firm, making
pulling away in water difficult and
dangerous.

Make sure that only small bow waves
are formed when driving the vehicle
through water.

Clean mud off the tire tread after
driving through water.

To dry the brakes, apply pressure to the
brake pedal several times after leaving
the water.Crossing obstacles
!Never accelerate before driving into the
water. The bow wave could force water into the
engine and auxiliary equipment, thus damaging
them.
!Do not open any of the vehicle’s doors while
driving through water. Water could otherwise en-
ter the vehicle interior and damage the vehicle’s
electronics, as well as the interior equipment.
!Obstacles can damage the vehicle
underbody or suspension components. If possi-
ble, use the assistance of a second person out-
side the vehicle to scout the path you intend to
take and check for adequate ground clearance
when you cross obstacles with your vehicle. The
person assisting you outside the vehicle should
always be a safe distance away from the vehicle
and positioned so that he or she cannot get hurt
in case of any unexpected vehicle movement.
After off-road driving or crossing obstacles,
inspect vehicle for any damage, especially
vehicle underbody and suspension components.
Failure to do so can adversely affect the vehi-
cle’s future performance, including increased
chance of an accident.

259 Operation
Driving instructions
When driving over tree stumps, big rocks
and other obstacles, observe the following
rules:

Check the vehicle clearance before
crossing obstacles.

Comply with the warnings
(
page 253) and rules for off-road
driving (
page 253).

Select gear range1 on the automatic
transmission (
page 167).

Cross obstacles very slowly by aiming
one of the front wheels at the center of
the obstacle, and repeat same with the
rear wheel.Driving on sand
When driving on sand, observe the
following rules:

Avoid high engine speeds.

Shift automatic transmission into a
gear range that is appropriate for the
terrain.

In sandy soil, drive at a steady speed as
conditions permit. This helps overcome
the vehicle rolling resistance and
reduce the likelihood of the vehicle
sinking into the ground.

Drive in tracks of other vehicles if they
are not too deep and you have suffi-
cient clearance.
Ruts
A number of off-road tracks or other
byways have deep ruts which can cause
the underbody to come in contact with the
ground.
!Special attention is needed when you cross
obstacles on a steep incline.
The vehicle could slide sideways as a result of its
possible slanted position which in turn may
result in the vehicle tipping or rolling over.
Warning!G
Do not reduce the tire inflation pressure
before driving through sand. However, if you
do so, remember to correct the tire inflation
pressure (
page 288) before continuing
your trip. Driving with reduced tire inflation
pressure increases the risk of losing control
of the vehicle and rolling over.
!Check that the ruts are not too deep and
your vehicle’s clearance is sufficient. Otherwise:

your vehicle may be damaged

the underbody of the vehicle may come in
contact with the ground and you may get
stuck

260 Operation
Driving instructions

Check the vehicle clearance before
driving in ruts.

Comply with the warnings
(
page 253) and rules for off-road
driving (
page 253).

Select gear range1 on the automatic
transmission (
page 167).

Drive slowly next to the ruts rather than
through them if at all possible.

If the ruts are too deep to drive in, drive
with one side of the vehicle on the
grassy center strip if the route permits.Returning from off-road drivingOff-road driving increases strain on the
vehicle.
We recommend that you inspect the vehi-
cle for possible damage after each off-road
trip. Recognizing any damage and a subse-
quent timely repair reduces the chance of
a possible breakdown or accident later on.
Proceed as follows:

Switch the transfer case in position
HIGH (
page 170).

Switch differential locks off
(
page 176).

Clean all exterior lamps and check
them for possible damage.

Clean the front and rear license plate.

Remove excessive dirt from tires,
wheels, wheel housings, and under-
body.
For instance, after driving in mud, clean
the radiator, chassis, engine, brakes,
and wheels from extreme dirt using a
strong jet of water.
After off-road driving or crossing obstacles,
inspect vehicle for any damage, especially
vehicle underbody and suspension components.
Failure to do so can adversely affect the vehi-
cle’s future performance, including increased
chance of an accident.
Warning!G
Never drive on pavement with activated
differential locks. Engaged front axle differ-
ential locks limits ability to move around
curves.
If you feel a sudden significant vibration or
ride disturbance, or you suspect that possi-
ble damage to your vehicle has occurred,
you should turn on the hazard warning flash-
ers, carefully slow down, and drive with cau-
tion to an area which is a safe distance from
the roadway.
Inspect the tires and under the vehicle for
possible damage. If the vehicle or tires
appear unsafe, have it towed to the nearest
Mercedes-Benz Light Truck Center or tire
dealer for repairs.
Damage to the vehicle may influence driving
comfort and poses the risk of accident to
you and other drivers.