check engine MERCEDES-BENZ G-CLASS SUV 2012 Owner's Guide

Display messages Possible causes/consequences and
M Solutions
DISTRONIC PLUS
currently unavail‐
able See Owner's
Manual DISTRONIC is deactivated and temporarily inoperative. Possible
causes:
R
the DISTRONIC PLUS cover in the radiator grille is dirty.
R the function is impaired due to heavy rain or snow.
R the sensors in the bumpers are dirty.
R the rada rsensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the transfer case is in the LOW RANGEtransmission position.
R the vehicle is on an uphill or downhill gradient of greater than
22%-25%.
R the on-board voltage is too low.
Aw arning tone also sounds.
If the display message does no tdisappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Engage the parking brake.
X Clean the DISTRONIC PLUS cover in the radiator trim and the
bumper (Y page 298).
X Restar tthe engine.
If the system detects that the sensors are fully operational, the
display message disappears.
DISTRONIC is operational again. DISTRONIC PLUS
inoperative DISTRONIC PLUS is faulty.
BAS might also have failed.
Aw
arning tone also sounds.
X Visi taqualified specialist workshop. DISTRONIC PLUS
suspended You have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.
X
Remove your foot from the accelerator pedal. DISTRONIC PLUS
--- km/h An activation condition for DISTRONIC PLUS is not fulfilled.
X
Check the activation conditions for DISTRONIC PLUS
(Y page 182). DISTRONIC PLUS and
SPEEDTRONIC
inoperative DISTRONIC PLUS and SPEEDTRONIC are faulty. A warning tone
also sounds.
X
Visit a qualified specialist workshop. 244
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
h
Tyre pressure
Check tyre(s) The tyre pressure in one or more tyres has dropped significantly.
G WARNING
With tyre pressures which are too low, there is a ris kofthe fol-
lowing hazards:
R the tyres may burst, especially as the load and vehicle speed
increase.
R the tyres may wear excessively and/or unevenly, which may
greatly impair tyre traction.
R the driving characteristics, as well as steering and braking, may
be greatly impaired.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
manoeuvres. Pay attention to the traffic conditions as you do
so.
X Secure the vehicle against rolling away (Y page 163).
X If there is a flat tyre, inspect the tyres (Y page 309).
X Check the tyre pressure (Y page 327).
X If necessary, correct the tyre pressure. h
Tyre pressure
Please correct The tyre pressure is too low in at least one of the tyres, or the tyre
pressure difference between the wheels is too great.
X
Check the tyre pressures at the next opportunity
(Y page 327).
X If necessary, correct the tyre pressure. Vehicle
Display messages Possible causes/consequences and
M Solutions
To start the
engine, shift to
either P or N You have attempted to start the engine with the transmission in
position
Ror D.
X Shift the transmission to position Por N. Auxiliary battery
malfunction The auxiliary battery for the automatic transmission is no longer
being charged.
X
Visit a qualified specialist workshop at the next opportunity.
X Until then, set the automatic transmission to position Pbefore
you switch off the engine.
X Before leaving the vehicle, apply the parking brake. 248
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M Solutions
D
Power
steering mal‐
function See Own‐
er's Manual The powe
rsteering assistance is faulty.
Aw arning tone also sounds.
G WARNING
You will need to use more force to steer.
There is a ris kofanaccident.
X Check whethe ryou are able to apply the extra force required.
X If you are able to steer safely: carefully drive on to a qualified
specialist workshop.
X If you are unable to steer safely: do not drive on. Contact the
nearest qualified specialist workshop. &
inoperative Bat‐
tery low You have attempted to switch on the auxiliary heating or to acti-
vate a departure time using the on-board computer after operating
the auxiliary heating twice.
X
Let the engine run for 10 seconds.
The auxiliary heating is operational again. The on-board voltage is too low. The auxiliary heating has switched
itself off or cannot be switched on (Y
page 126).
X Drive for a longer distance.
The battery is being charged. The auxiliary heating is operational
again as soon as the on-board electrical system voltage is suf-
ficient. &
inoperative Refuel there is too little fuel in the fuel tank.T
he auxiliary heating cannot
be switched on (Y page 126).
X Refuel at the nearest filling station. &
inoperative See
Owner's Manual The auxiliary heating has a temporary malfunction or is faulty.
X
When the vehicle is on alevel surface and the engine has cooled
down, make up to four attempts to switch on the auxiliary heat-
ing, waiting several minutes between each attempt
(Y page 126).
X If the auxiliary heating does not switch on, consult a qualified
specialist workshop. 250
Display messagesOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
÷
The yellow ESP
®
warn-
ing lamp flashes while
the vehicle is in motion. ESP
®
or traction control has intervened because there is a risk of
skidding or at least one wheel has started to spin.
Cruise control or DISTRONIC PLUS is deactivated.
X Only depress the accelerator pedal as far as necessary when
pulling away.
X Accelerate more gently while the vehicle is in motion.
X Adapt your driving style to suit the road and weather conditions.
X Do not deactivate ESP ®
.
Exceptions: (Y page 62) å
The yellow ESP
®
OFF
warning lamp is lit while
the engine is running. ESP
®
is deactivated.
G WARNING
If ESP ®
is switched off, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Reactivate ESP ®
.
Exceptions: (Y page 62)
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Have ESP ®
checked at a qualified specialist workshop. ֌
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
, BAS, the HOLD function, hill start assist, the adaptive brake
lights and ESP ®
trailer stabilisation are not available due to a mal-
function.
G WARNING
The brake system continues to function normally, but without the
functions listed above.
The braking distance in an emergency braking situation can thus
increase.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
The danger of skidding and having an accident increases.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
257On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
!
The yellow parking
brake warning lamp
comes on while the
vehicle is moving. A
warning tone also
sounds.
You are driving with the parking brake applied.
X
Release the parking brake.
The warning lamp goes out and the warning tone ceases. 6
The red SRS warning
lamp is lit while the
engine is running.
There is a malfunction in the SRS (Supplemental Restraint Sys-
tem).
G WARNING
The airbags or belt tensioners may either be triggered uninten-
tionally or, in the event of an accident, may not be triggered.
This poses an increased risk of injury.
X Drive on carefully.
X Have SRS checked at a qualified specialist workshop immedi-
ately.
For further information about the Supplemental Restraint System,
see (Y page 39). Engine
Problem Possible causes/consequences and
M Solutions
;
The yellow engine diag-
nostics warning lamp
lights up while the
engine is running.
There may be a fault, for example:
R
in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system (for vehicles with petrol engines)
R in the fuel system
The emission limit values may be exceeded and the engine may
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop. ;
The yellow engine diag-
nostics warning lamp
lights up while the
engine is running.
Vehicles with a diesel engine: the fuel tank has been run dry
(Y
page 159).
X Start the engine three to four times after refuelling.
If the yellow engine diagnostics warning lamp goes out, emer-
gency running mode is cancelled. The vehicle need not be
checked. Warning and indicator lamps in the instrument cluster
259On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator
may be blocked or the electric engine radiator fan may be mal-
functioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X
Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Engage the parking brake.
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and top up the coolant, observing the
warning notes (Y page 293).
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X Do not start the engine again until the coolant temperature is
below 120 †. The engine may otherwise be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain, and stop-start driving. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 120 †. The airflow to the
engine radiator may be blocked or the coolant level may be too
low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Never drive with an overheated engine. Driving when your engine
is overheated can cause some fluids which may have leaked into
the engine compartment to catch fire.
Steam from an overheated engine can cause serious burns which
can occur just by opening the bonnet.
There is a risk of injury.
X Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Secure the vehicle against rolling away (Y page 163).Warning and indicator lamps in the instrument cluster
261On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
X
Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and top up the coolant, observing the
warning notes (Y page 293).
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in moun-
tainous terrain and stop-start driving. Driving systems
Problem Possible causes/consequences and
M Solutions
·
The red distance warn-
ing lamp lights up while
the vehicle is in motion. The distance to the vehicle in front is too small for the speed
selected.
X
Increase the distance. ·
The red distance warn-
ing lamp lights up while
the vehicle is in motion.
Aw arning tone also
sounds. You are approaching a vehicle or a stationary obstacle in your line
of travel at too high a speed.
X
Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to
brake or take evasive action.
Further information on DISTRONIC PLUS (Y page 182).262
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Opens the bonnet
The release lever on the bonnet is in the foot-
well on the left-hand side of the vehicle when
viewed in the direction of travel.
X Make sure that the windscreen wipers are
switched off.
X Pull release lever :on the bonnet.
The bonnet is released. Vehicles with a petrol engine
Vehicles with a diesel engine X
Lift the bonnet slightly.
X Petrol engine: push the handle of bonnet
catch ;in the direction of the arrow and
lift the bonnet.
X Diesel engine: pull the handle of bonnet
catch ;in the direction of the arrow and
lift the bonnet.
Closing the bonnet G
WARNING
Make sure that nobody can become trapped
as you close the bonnet.
X Lower the bonnet and let it fall from a
height of approximately 20 cm.
X Check that the bonnet has engaged prop-
erly.
If the bonnet can be raised slightly, it is not
properly engaged. Open it again and close
it with a little more force. Radiator
i Vehicles with adiesel engine: do not
cover the radiator. Do not use thermal
mats, insect protection covers or anything
similar. Doing so can cause the Onboard
Diagnostics System to display inaccurate
values. Some of these values are legally
required and must always be correct. Engine oil
Notes on oil level Depending on your driving style, the vehicle
consumes up to 0.
8lof oil per 1,000 km. The
oil consumption may be higher than this when
the vehicle is new or if you frequently drive at
high engine speeds. Engine compartment
291Maintenance and care Z

Checking the oil level using the oil dip-
stick
Example
:oil dipstick
On the G 65 AMG, the oil level can be checked
using the on-board computer only.
On all other models, the dipstick must be
used to chec kthe engine oil level.
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.
R the engine should be switched off for at
least 30 minutes if the engine is not at
operating temperature (i.e. if you only start
the engine briefly).
X Pull oil dipstick :out of the oil dipstick
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 Top up the oil if necessary.
Checking the oil level using the on-
board computer !
Do not add too much oil. Topping up with
too much engine oil can result in damage
to the engine or to the catalytic converter.
Have excess engine oil siphoned off.
G6 5 AMG: the oil level can be checked using
the on-board computer only. On all other models, the dipstic
kmust be
used to chec kthe engine oil level.
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 key is in position 2in
the ignition lock.
X Press the &or* button on the steer-
ing 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 l to reach maximum oil level
R
Add 1.5 litres to reach maximum oil level
R
Add 2.0 l to reach maximum oil level
X
Top up the oil if necessary.
If the engine is at normal operating tempera-
ture and the Engine oil Reduce oil level message appears, the engine oil level
is too high.
X Have excess oil siphoned off.
If the Switch ignition on to check engine oil level message appears:
X Turn the key to position 2in the ignition
lock (Y page 143).
If the Observe waiting time message
appears: 292
Engine compartmentMaintenance and care

X
If the engine is at normal operating tem-
perature: repeat the measuremen tafter
about five minutes.
X 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 when engine on message appears:
X Switch off the engine.
X If the engine is at normal operating tem-
perature: wait about five minutes before
carrying out the measurement.
X If the engine is not at normal operating
temperature: e.g. if the engine was only
started briefly, wait approximately
30 minutes before carrying out the meas-
urement.
i If you wish to cancel the measurement,
press the *or& button on the mul-
tifunction steering wheel.
Adding engine oil H
Environmental note
When topping up the oil, take care not to spill
any. If oil enters the soil or waterways, it is
harmful to the environment.
! Do not add too much oil .Ifthe oil level is
above the "max" mark on the dipstick, too
much oil has been added. This can lead to
damage to the engine or the catalytic con-
verter. Have excess oil siphoned off. Engine oil cap (example:
G 65 AMG) X
Turn cap :anti-clockwise and remove it.
X Top up with the amount of oil required.
Observe the specifications in the on-board
computer when doing so or fill carefully to the
maximum mark on the oil dipstick.
For further information on engine oil, see
(Y page 345).
i The difference between the minimum
mark and the maximum mark on the oil
dipstick is approximately 2litres.
X Replace cap :on the filler neck and
tighten clockwise.
Make sure that the cap locks securely into
place. Other service products
Checking the coolant level G
WARNING
The cooling system is pressurised. Therefore,
only unscrew the cap once the engine has
cooled down. The coolan ttemperature dis-
play must be less than 70 †. Otherwise, you
could be scalded if hot coolant escapes. X
Park the vehicle on a level surface.
Only chec kthe coolant level if the vehicle
is on a level surface and the engine has
cooled down.
X Turn the key to position 2(Ypage 143) in
the ignition lock. Engine compartment
293Maintenance and care Z