2015 MERCEDES-BENZ G-Class fuel pressure

Display messages
Possible causes/consequences and
M
MSolutions Telephone No Ser‐
Telephone No Ser‐
vice vice Your vehicle is outside the network provider's transmitter/
receiver range.
X Wait until the mobile phone operational readiness symbol
appears in the multifunction display. ¥
Check Washer Fluid Check Washer Fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
X Add washer fluid (Y page 278).SmartKey
Display messages
Possible causes/consequences and
M MSolutions Â
Key Does Not Key Does Not
Belong to Vehicle Belong to Vehicle You have put the wrong SmartKey in the ignition lock.
X Use the correct SmartKey. Â
Take Take
Your
YourKey
Keyfrom
from
Ignition
Ignition The SmartKey is in the ignition lock.
X Remove the SmartKey. Â
Obtain a New Key Obtain a New Key The SmartKey needs to be replaced.
X Visit a qualified specialist workshop. Warning and indicator lamps in the
instrument cluster Overview of warning and indicator
lamps
L Low-beam headlamps (Y page 99)
#
! Turn signal (Y
page 103)
K High-beam headlamps
(Ypage 103)
N Front fog lamps (Y page 101)
R Rear fog lamp (Y page 101)
ü Seat belts (Y page 235)
$
(USA) Braking (Y
page 236) J
(Can-
ada)
Brakes (yellow) (Y
page 236)
! ABS (Ypage 237)
÷ ESP®
(Y page 239)
å ESP®
OFF (Y page 239)
6 Restraint system (Y page 242)
; Check engine (Y page 243)
8 Reserve fuel (Y page 243)
? Coolant (Y page 243)
· Distance warning signal
(Ypage 245)
h Tire pressure monitor
(Ypage 246) 234
Wa
rning and indi cator lamps in the instrument clusterOn-board computer and displays

Engine
Problem
Possible causes/consequences and
M
MSolutions ;
The yellow Check
Engine warning lamp
lights up while the
engine is running.
There may be a malfunction, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system
R in the fuel system
The emission limit values may be exceeded and the engine may be
in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states, you must immediately visit a qualified special-
ist workshop as soon as the yellow Check Engine warning lamp
lights up. This is due to the legal requirements in effect in these
states. If in doubt, check whether such legal regulations apply in the state in which you are currently driving. 8
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.
The fuel level has dropped into the reserve range.
X Refuel at the nearest gas station. 8
The yellow reserve fuel
warning lamp flashes
while the vehicle is in
motion.
In addition, the
;
Check Engine warning
lamp may light up. The fuel system pressure is too low. The fuel filler cap is not closed
correctly or the fuel system is leaking.
X Check that the fuel filler cap is correctly closed.
X If the fuel filler cap is not correctly closed: close the fuel filler
cap.
X If the fuel filler cap is closed: visit a qualified specialist work-
shop. ?
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature gage is at the
start of the scale. The temperature sensor for the coolant temperature gage is defec-
tive.
The coolant temperature is no longer being monitored. There is a risk of engine damage if the coolant temperature is too high.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions. Do not continue
driving under any circumstances.
X Apply the parking brake.
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
243On-board computer and displays Z

Useful information
i This Operator's Manual describes all
models and all standard and optional equip- ment of your vehicle available at the time of
publication of the Operator's Manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
i Read the information on qualified special-
ist workshops: (Y page 24). Important safety notes
G
WARNING
If wheels and tires of the wrong size are used, the wheel brakes or suspension components
may be damaged. There is a risk of an acci-
dent.
Always replace wheels and tires with those
that fulfill the specifications of the original
part.
When replacing wheels, make sure to use the
correct:
R designation
R model
When replacing tires, make sure to use the
correct:
R designation
R manufacturer
R model G
Warning
A flat tire severely impairs the driving, steer-
ing and braking characteristics of the vehicle.
There is a risk of an accident.
do not drive with a flat tire. Immediately
replace the flat tire with your spare wheel, or
consult a qualified specialist workshop.
Contact an authorized Mercedes-Benz Center if you require information on tested and rec- ommended wheels and tires for summer and
winter driving. Advice on purchasing and car-
ing for tires is also available there.
Accessories that are not approved for your
vehicle by Mercedes-Benz or are not being
used correctly can impair the operating
safety.
Before purchasing and using non-approved
accessories, visit a qualified specialist work-
shop and ask about:
R suitability
R legal stipulations
R factory recommendations
Information on the dimensions and types of
wheels and tires for your vehicle can be found
in the "Wheel/tire combinations" section
(Y page 331).
Information on air pressure for the tires on
your vehicle can be found:
R on the tire pressure label on the fuel filler
flap
R in the "Tire pressure" section
i Further information on wheels and tires
can be obtained at any qualified specialist
workshop. Operation
Notes on driving
If the vehicle is heavily loaded, check the tire pressures and correct them if necessary.
When parking your vehicle, make sure that
the tires do not get deformed by the curb or
other obstacles. If it is necessary to drive over
curbs, speed humps or similar elevations, try to do so slowly and at an obtuse angle. Oth-
erwise, the tires, particularly the sidewalls,
may be damaged. 306
OperationWheels and tires

R
before beginning a long journey
R under different operating conditions, e.g.
off-road driving
If necessary, correct the tire pressure.
i The specifications on the sample Tire and
Loading Information placard and tire pres-
sure tables are examples. Tire pressure
specifications are vehicle-specific and may
deviate from the data shown here. The tire pressure specifications that are valid for
your vehicle can be found on the Tire and
Loading Information placard and tire pres-
sure table on the vehicle.
General notes The recommended tire pressures for the tires
mounted at the factory can be found on the
labels described here.
Operation with a trailer: the applicable
value for the rear tires is the maximum tire
pressure value stated in the table inside the
fuel filler flap.
Further information on tire pressures can be
obtained at a qualified specialist workshop.
Tire and Loading Information placard :
Recommended tire pressures
The Tire and Loading Information placard is
on the B-pillar on the driver's side
(Y page 316).
The Tire and Loading Information placard con-
tains the recommended tire pressures for
cold tires. The recommended tire pressures are valid for the maximum permissible load
and up to the maximum permissible vehicle
speed.
Tire pressure table Example: tire pressure table for all tires permitted
for this vehicle by the factory
The tire pressure table is on the inside of the fuel filler flap.
The tire pressure table contains the recom-
mended pressures for cold tires for various
operating conditions, i.e. differing load and
speed conditions.
If a tire size precedes a tire pressure, the tire
pressure information following is only valid
for that tire size. The load conditions "partially laden" and "fully laden" are defined in the
table for different numbers of occupants and
amounts of luggage. The actual number of
seats may differ.
Some tire pressure tables only show the rim
diameter instead of the complete tire size,
e.g. R16. Rim diameter is part of the tire size
and can be found on the tire sidewall
(Y page 321).
If the tire pressures have been set to the
lower values for lighter loads and/or lower
road speeds, the pressures should be reset to
the higher values:
R if you want to drive with an increased load
and/or
R if you want to drive at higher road speeds
i The tire pressures for increased loads
and/or higher road speeds, shown in the 310
Tire pressureWheels and tires

tire pressure table, may have a negative
effect on driving comfort.
If the tire pressure is not set correctly, this
can lead to an excessive build up of heat and
a sudden loss of pressure.
For more information, contact a qualified spe- cialist workshop. Important notes on tire pressure
G
WARNING
If the tire pressure drops repeatedly, the
wheel, valve or tire may be damaged. Tire
pressure that is too low may result in a tire
blow-out. There is a risk of an accident.
R Check the tire for foreign objects.
R Check whether the wheel is losing air or the
valve is leaking.
If you are unable to rectify the damage, con-
tact a qualified specialist workshop. G
WARNING
If you fit unsuitable accessories onto tire
valves, the tire valves may be overloaded and malfunction, which can cause tire pressure
loss. Due to their design, retrofitted tire pres- sure monitors keep the tire valve open. This
can also result in tire pressure loss. There is a
risk of an accident.
Only screw the standard valve cap or other
valve caps approved by Mercedes-Benz for
your vehicle onto the tire valve.
Use a suitable pressure gauge to check the
tire pressure. The outer appearance of a tire
does not permit any reliable conclusion about the tire pressure. On vehicles equipped with
the electronic tire pressure monitoring sys-
tem, the tire pressure can be checked using
the on-board computer.
The tire temperature and pressure increase
when the vehicle is in motion. This is depend-
ent on the driving speed and the load.
Therefore, you should only correct tire pres-
sures when the tires are cold. The tires are cold:
R if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
R if the vehicle has been driven for less than
1 mile (1.6 km).
The tire temperature changes depending on
the outside temperature, the vehicle speed
and the tire load. If the tire temperature
changes by 18 ‡ (10 †), the tire pressure
changes by approximately 10 kPa (0.1 bar/
1.5 psi). Take this into account when check-
ing the pressure of warm tires. Only correct
the tire pressure if it is too low for the current
operating conditions. If you check the tire
pressure when the tires are warm, the result- ing value will be higher than if the tires were
cold. This is normal. Do not reduce the tire
pressure to the value specified for cold tires. The tire pressure would otherwise be too low.
Observe the recommended tire pressures for
cold tires:
R on the Tire and Loading Information placard
on the B-pillar on the driver's side
R in the tire pressure table on the inside of the
fuel filler flap
Observe the following for the tire pressure on the spare wheel:
R the tire and loading information table on
the B-pillar on the driver's side.
R the tire pressure sticker on the inside of the
fuel filler flap. Underinflated or overinflated tires
Underinflation G
WARNING
Tires with pressure that is too low can over-
heat and burst as a consequence. In addition, they also suffer from excessive and/or irreg-
ular wear, which can severely impair the brak-ing properties and the driving characteristics.There is a risk of an accident. Tire pressure
311Wheels and tires
Z

Avoid tire pressures that are too low in all the
tires, including the spare wheel.
Underinflated tires may: R overheat, leading to tire defects
R have an adverse effect on handling charac-
teristics
R wear quickly and unevenly
R have an adverse effect on fuel consumption
Overinflation G
WARNING
Tires with excessively high pressure can burst
because they are damaged more easily by
road debris, potholes etc. In addition, they
also suffer from irregular wear, which can
severely impair the braking properties and the driving characteristics. There is a risk of an
accident.
Avoid tire pressures that are too high in all the
tires, including the spare wheel.
Overinflated tires may: R increase the braking distance
R have an adverse effect on handling charac-
teristics
R wear quickly and unevenly
R have an adverse effect on ride comfort
R be more susceptible to damage
Maximum tire pressures :
Example: maximum permissible tire pres-
sure Never exceed the maximum permissible tire
inflation pressure. Always observe the rec-
ommended tire pressure for your vehicle
when adjusting the tire pressure
(Y page 325).
i The actual values for tires are vehicle-
specific and may deviate from the values in
the illustration. Checking the tire pressures
Important safety notes Observe the notes on tire pressure
(Y page 309).
Information on air pressure for the tires on
your vehicle can be found:
R on the tire pressure label on the fuel filler
flap (Y page 310)
R in the "Tire pressure information" section
R in the "Tire pressure data" section
(Y page 309)
Checking tire pressures manually To determine and set the correct tire pres-
sure, proceed as follows:
X Remove the valve cap of the tire that is to
be checked.
X Press the tire pressure gauge securely onto
the valve.
X Read the tire pressure and compare it to
the recommended value on the Tire and
Loading Information placard on fuel filler
flap of your vehicle (Y page 310).
X The tire pressure is too low: increase the
tire pressure to the recommended value.
X The tire pressure is too high: press down
the metal pin in the valve using the tip of a
pen, for example.
Air is released from the tire.
X Check the tire pressure again with the tire
pressure gauge.
X Screw the valve cap onto the valve.
X Repeat these steps for the other tires. 312
Tire pressureWheels and tires

Tire pressure monitor
Important safety notes G
WARNING
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the pressure rec-
ommended by the vehicle manufacturer on
the Tire and Loading Information placard on
the driver's door B-pillar or the tire pressure
label on the inside of the fuel filler flap. If your vehicle has tires of a different size than the
size indicated on the Tire and Loading Infor-
mation placard or the tire pressure label, you should determine the proper tire pressure for
those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring system (TPMS) that illuminates a low tire pres-
sure telltale when one or more of your 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 underin-
flated tire causes the tire to overheat and can lead to tire failure. Underinflation also
reduces fuel efficiency and tire tread life, andmay affect the vehicle's handling and stop-
ping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the driv-
er'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 if 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 warning lamp will
flash for approximately a minute and then
remain continuously illuminated. This
sequence will be repeated every time the vehi- cle 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 malfunc- tions may occur for a variety of reasons,
including the mounting of incompatible
replacement or alternate tires or wheels on
the vehicle that prevent the TPMS from func-
tioning properly. Always check the TPMS mal-
function 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 prop-
erly.
It is the driver's responsibility to set the tire
pressure to the recommended cold tire pres-
sure suitable for the operating situation
(Y page 309). Note that the correct tire pres-
sure for the current operating situation must
first be taught-in to the tire pressure monitor. If there is a substantial loss of pressure, the
warning threshold for the warning message is aligned to the reference values taught-in.
Restart the tire pressure monitor after adjust-
ing to the cold tire pressure (Y page 315).
The current pressures are saved as new ref-
erence values. As a result, a warning message will appear if the tire pressure drops signifi-
cantly.
The tire pressure monitor does not warn you
of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(Y page 309).
The tire pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tire is penetrated by a foreign object. In the
event of a sudden loss of pressure, bring the
vehicle to a halt by braking carefully. Avoid
sudden steering movements.
In order to check the tire pressure, the vehi-
cle's wheels are installed with sensors that
monitor the tire pressure in all four tires. The tire pressure monitor warns you if the pres-
sure drops in one or more of the tires. The tire Tire pressure
313Wheels and tires Z

Monitor Active
Monitor Active
display message is shown
instead of the tire pressure display. The tire
pressures are already being monitored.
i If a spare wheel is mounted, the system
may continue to show the tire pressure of
the wheel that has been removed for a few minutes. Observe that the displayed value
is not the same as the current tire pressure
of the emergency spare wheel.
Tire pressure monitor warning mes-
sages If the tire pressure monitor detects a signifi-
cant pressure loss on one or more tires, a
warning message is shown in the multifunc-
tion display. A warning tone also sounds and
the tire pressure warning lamp lights up in the
instrument cluster.
Each tire that is affected by a significant loss of pressure is highlighted in the pressure dis-
play.
X If the Correct Tire Pressure
Correct Tire Pressure message
appears in the multifunction display, check the tire pressure on all four wheels and cor-
rect it if necessary.
X If the Check
Check Tires Tiresmessage appears in the
multifunction display, the tire pressure in
one or more tires has dropped significantly and the tires must be checked.
X If the Tire Press. Warning Caution
Tire Press. Warning Caution
Tire Malfunction
Tire Malfunction message appears in
the multifunction display, the tire pressure in one or more tires has dropped suddenly
and the tires must be checked.
i If the wheel positions on the vehicle are
rotated, the tire pressures may be dis-
played for the wrong positions for a short
time. This is rectified after a few minutes of driving, and the tire pressures are displayed
for the correct positions.
Restarting the tire pressure monitor When you restart the tire pressure monitor, all
existing warning messages are deleted and the warning lamps go out. The monitor uses
the currently set tire pressures as the refer-
ence values for monitoring. In most cases, the
tire pressure monitor will automatically
detect the new reference values after you
have changed the tire pressure. However, you
can also define reference values manually as described here.
X Set the tire pressure to the value recom-
mended for the corresponding driving sit-
uation on the Tire and Loading Information
placard on the driver's side
B-pillar (Y page 309).
Additional tire pressure values for different loads can also be found on the tire pressure table on the inside of the fuel filler flap
(Y page 309).
X Make sure that the tire pressure is correct
on all four wheels.
X Make sure that the SmartKey is in position
2 in the ignition lock (Y page 133).
X Press the =or; button on the steer-
ing wheel to select the Serv. Serv.menu.
X Press the 9or: button to select
Tire Pressure
Tire Pressure.
X Press the abutton.
The multifunction display shows the cur-
rent tire pressure for the individual tires or
the Tire
Tire pressure
pressure will
willbe
bedisplayed
displayed
after driving a few minutes
after driving a few minutes mes-
sage.
X Press the :button.
The Use Current Pressures as New
Use Current Pressures as New
Reference Values
Reference Values message appears in
the multifunction display.
If you wish to confirm the restart:
X Press the abutton.
The Tire Press. Monitor Restarted
Tire Press. Monitor Restarted
message appears in the multifunction dis-
play.
After driving for a few minutes, the system
checks whether the current tire pressures
are within the specified range. The new tire
pressures are then accepted as reference
values and monitored. Tire pressure
315Wheels and tires Z