2012 MERCEDES-BENZ G-Class stop start

Display messages Possible causes/consequences and
M Solutions?
Coolant
Stop,
Turn
Engine Off The coolant is too hot.
X
Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Make sure that the air supply to the radiator is not blocked, e.g.
by snow, slush or ice.
X Wait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.
X Pay attention to the coolant temperature display.
X If the temperature increases again, visit a qualified specialist
workshop immediately. The poly-V-belt may have torn.
X
Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Open the hood.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not

continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is not damaged:
X Wait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.
X Pay attention to the coolant temperature display.
X Visit a qualified specialist workshop. G
WARNING
Driving when your engine is overheated can cause some fluids which may have leaked into the
engine compartment to catch fire. You could be seriously burned.
Steam from

an overheated engine can cause serious burns which can occur just by opening the
engine hood. Stay away from the engine if you see or hear steam coming from it.
Stop the vehicle in a safe location away from other traffic. Turn off the engine, get out of the
vehicle and do not stand near the vehicle until the engine has cooled down.
! If the coolant temperature exceeds 248 ‡(120 †) do not continue driving. The engine will
otherwise be damaged. Display messages
171
On-board computer and displays Z

Display messages Possible causes/consequences and
M Solutions? The engine fan is defective.
X
At coolant temperatures under 248 ‡ (120 † ), drive to the next
qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic. # The battery is not being charged.
Possible causes are:
R
a defective alternator
R a torn poly-V-belt
R a malfunction in the electronics
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Open the hood.
X Check whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not

continue driving. The engine could otherwise overheat.
X Consult a qualified specialist workshop.
If the poly-V-belt is not damaged:
X Visit a qualified specialist workshop. The battery voltage is too low.
X
Switch off electrical consumers that are not required.
X Have the battery and alternator checked at a qualified specialist
workshop. The battery has been charged or the vehicle has been jump-
started.
X
Have the battery and alternator checked at a qualified specialist
workshop. 4
Check
oil

level at
next gas station. The engine oil level has dropped to a critical level.
X
Check the oil level (Y page 211).
X If necessary, add engine oil ( Y page 213).
X Have the engine checked for leaks if the engine oil needs to be
refilled more often than usual. You have added too much engine oil. There is a risk of damaging
the engine or catalytic converter.
X
Siphon off excess engine oil until it is at the specified level.
Observe the legal requirements.172
Display messages
On-board computer and displays

Tires
G
WARNING
Do not drive with a flat tire. A flat tire affects the ability to steer or brake the vehicle. You may
lose control of the vehicle. Continued driving with a flat tire will cause excessive heat build-up
and possibly a fire. G
WARNING
Follow recommended tire inflation pressures.
Do not
underinflate tires. Underinflated tires wear excessively and/or unevenly, adversely affect
handling and fuel economy, and are more likely to fail from being overheated.
Do not overinflate tires. Overinflated tires can adversely affect handling and ride comfort, wear
unevenly, increase stopping distance, and result in sudden deflation (blowout) because they are
more likely to become punctured or damaged by road debris, potholes etc. Display messages Possible causes/consequences and
M
Solutions
Tire pressure
displayed only
after driving for
a few minutes The tire pressure monitor is measuring the tire pressure.
X
Drive on.
The tire

pressures appear in the multifunction display after you
have been driving for a few minutes. Tire Pres.
Check Tires
G
Risk of accident
The
tire pressure monitor has detected a significant pressure loss.
X Stop the vehicle without making any sudden steering or braking
maneuvers. Pay

attention to the traffic conditions as you do so.
X Check the tires.
X Check the tire pressure and correct it if necessary
(Y page 242).
X Repair or change the faulty wheel as necessary ( Y page 226).
X Then restart the tire pressure monitor when the tire pressure is
correct (

Y page 249). Tire Pres. Monitor
Inoperative The tire pressure monitor is deactivated due to a malfunction.
X
Visit a qualified specialist workshop. Tire Pres. Monitor
Inoperative No
Wheel Sensors The wheels mounted do not have a suitable tire pressure sensor.
The tire pressure monitor is deactivated.
X
Mount wheels with suitable tire pressure sensors.
The tire

pressure monitor is activated automatically after driving
for a few minutes. Display messages
175
On-board computer and displays Z

Display messages Possible causes/consequences and
M SolutionsCaution Tire Defect
G
Risk of accident
The tire pressure in one or more tires has dropped suddenly. The
wheel position is shown in the multifunction display.
X Stop the vehicle without making any sudden steering or braking
maneuvers. Pay
attention to the traffic conditions as you do so.
X If necessary, change a wheel ( Y page 226).Correct The
Tire Pres. The tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great.
X
Check the tire pressures at the next opportunity. If necessary,
correct the tire pressure ( Y page 245).
X Restart the tire pressure monitor (Y page 251). Wheel Sensor
Missing There is no signal from the tire pressure sensor of one or several
wheels. The pressure of the affected tire is not displayed in the
multifunction display.
X
Have the faulty tire pressure sensor replaced at a qualified
specialist workshop. Tire Pres. Monitor
Currently
Unavailable Due to a source of radio interference, no signals can be received
from the wheel sensors. The tire pressure monitor is temporarily
malfunctioning.
X
Drive on.
The tire

pressure monitor restarts automatically as soon as the
problem has been solved. h
Correct The Tire
Pres. The tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great.
X
Check the tire pressures at the next opportunity. If necessary,
correct the tire pressure ( Y page 248).176
Display messages
On-board computer and displays

Make sure any children traveling with you do
not injure themselves or start a fire with the
hot cigarette lighter.
! The 12 V socket in the cigarette lighter
can be used for accessories (up to a
maximum of 180 W), as long as they have
the standard socket type for cigarette
lighters. Note that the socket in the
cigarette lighter can be damaged when
connecting accessories, for example by
frequent insertion and removal or by
sockets that
do not fit correctly. A damaged
socket can cause the cigarette lighter to
stop working. X
Press cover
; and then release it.
The ashtray and cigarette lighter : fold
out.
X Press in cigarette lighter :.
Cigarette lighter : will pop out
automatically when the heating element is
red-hot. 12 V sockets
Points to observe before use !
If you are simultaneously using all three
sockets in the vehicle, make sure that you
do not exceed the maximum current draw
of 45 A. Otherwise, you will overload the
fuses.
The sockets

can be used for accessories with
a maximum power consumption of 180 W (15
A), e.g. lamps or chargers for mobile phones. If you use the sockets for long periods when
the engine is switched off, the battery may
discharge.
X
Turn the SmartKey to position 2 in the
ignition lock.
Socket in the front-passenger footwell X
Lift up the cover of the socket.
The
cigarette lighter socket can be also used
(Y page 195). This is the case even if the
SmartKey has

been removed from the ignition
lock.
Socket in the rear compartment The socket is located on the center console
in the rear compartment.
X
Lift up the cover of the socket.
Socket in the cargo compartment The socket is located in the cargo
compartment on the left-hand side, when
viewed in the direction of travel, next to the
rear door.196
Features
Stowing and features

X
Pull oil dipstick : out of the dipstick guide
tube.
X Wipe off oil dipstick :.
X Slowly slide oil dipstick : into the guide
tube to the stop, and take it out again.
The oil

level is correct if the level is between
MIN mark = and MAX mark ;.
X Add oil if necessary.
Checking the oil level using the on-
board computer On the G 55 AMG, the oil level can be checked
using the on-board computer.
When checking the oil level:
R
park the vehicle on a level surface.
R the engine should be switched off for
approximately five minutes if the engine is
at normal operating temperature.
X Make sure that the SmartKey is in position
2 in the ignition lock.
X Press the & or * button on the
steering wheel to select the following
message: The measurement takes a few seconds. You
will
see

one of the following messages in the
multifunction display:
R Engine Oil Level OK
R Add 1.0 qt (Canada: 1.0 liter) to
reach maximum oil level. R
Add 1.5 qts (Canada: 1.5 liters) to
reach maximum oil level.
R Add 2.0 qts (Canada: 2.0 liters) to
reach maximum oil level.
X Add oil if necessary.
If the engine is at normal operating
temperature and the Engine Oil Reduce
Oil Level message appears, the engine oil
level is too high.
X Have excess oil siphoned off.
! Do not

add too much oil. Adding too much
oil can result in damage to the engine or the
catalytic converter. Have excess oil
siphoned off.
If the Switch ignition on to check
engine oil level message appears:
X Turn the SmartKey to position 2 in the
ignition lock.
If the Observe Waiting Time message
appears:
X If the engine is at normal operating
temperature: repeat the measurement
after about five minutes.
If the engine is not at normal operating
temperature (e.g. if the engine was only
started briefly): repeat the measurement
after about 30 minutes.
If the Engine Oil Level Not With
Engine On message appears:
X Switch off the engine.
X If the engine is at normal operating
temperature: wait about five minutes
before carrying out the measurement.
If the engine is not at normal operating
temperature, e.g. if the engine was only
started briefly: wait about 30 minutes
before carrying out the measurement.
i If you wish to cancel the measurement,
press the * or & button on the
multifunction steering wheel. 212
Engine compartment
Maintenance and care

tires are significantly underinflated.
Accordingly, when the low tire pressure
telltale
illuminates,
you should stop and check
your tires as soon as possible, and inflate
them to the proper pressure. Driving on a
significantly underinflated tire causes the tire
to overheat and can lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle's
handling and stopping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the
driver's responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
USA only:
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined with
the low tire pressure telltale. When the
system detects a malfunction, the telltale will
flash for approximately one minute and then
remain continuously illuminated. This
sequence will be repeated every time the
vehicle is started as long as the malfunction
exists.
When the malfunction indicator is illuminated,
the system may not be able to detect or signal
low tire pressure as intended. TPMS
malfunctions may occur for a variety of
reasons, including the installation of
incompatible replacement or alternate tires
or wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on your
vehicle to ensure that the replacement or
alternate tires and wheels allow the TPMS to
continue to function properly.
i USA only:
If the tire pressure monitor is
malfunctioning, it may take more than
10 minutes for the tire pressure warning
lamp to inform you of the malfunction by flashing for 60 seconds and then remaining
lit.
When the malfunction has been rectified,
the tire pressure warning lamp goes out
after driving for a few minutes.
Information on tire pressures is displayed in
the multifunction
display. After a few minutes
of driving, the current tire pressure of each
tire is shown in the multifunction display.
i The tire pressure values indicated by the
on-board computer may differ from those
measured at a gas station with a pressure
gauge. The tire pressures shown by the on-
board computer refer to those measured at
sea level. At high altitudes, the tire pressure
values indicated by a pressure gauge are
higher than those shown by the on-board
computer. In this case, do not reduce the
tire pressures.
i The operation of the tire pressure monitor
can be affected by interference from radio
transmitting equipment (e.g. radio
headphones, two-way radios) that may be
being operated in or near the vehicle.
i USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
i Canada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference,
and 250
Tire pressure
Wheels and tires