ECU MERCEDES-BENZ G-CLASS 2018 Manual PDF

displayed after driving a few minutesmessage appears.
After a teach-in process, the tire pressure mon-
itor automatically detects new wheels or new
sensors. As long as a clear allocation of the tire
pressure value to the individual wheels is not
possible, theTire
PressureMonitorActivedisplay message is shown instead of the tire
pressure display. The tire pressures are already
being monitored.
If a spare wheel is installed, the system may
continue to show the tire pressure of the wheel
that has been removed for a few minutes. Please
note that in this case, the value displayed for the
replaced wheel does not indicate the current
tire pressure of the spare wheel.
Tire pressure monitor warning mes-
sages
If the tire pressure monitor detects a pressure
loss in one or more tires, a warning message is
shown in the multifunction display. The yellow
htire pressure warning lamp then lights up.
RIf the Correct Tire Pressuremessage
appears in the multifunction display, the tire
pressure in at least one tire is too low. The tire
pressure must be corrected when the oppor-
tunity arises.
RIf the Check Tiresmessage appears in the
multifunction display, the tire pressure in at
least one tire has dropped significantly. The
tires must be checked.
RIf the Caution - Tire Malfunc.message
appears in the multifunction display, the tire
pressure in at least one tire has dropped sud-
denly. The tires must be checked.
Be sure to observe the instructions and safety
notes in the display messages in the "Tires" sec-
tion (
Ypage 187).
If the position of the wheels on the vehicle is
changed, the tire pressure may be displayed in
the wrong positions for a short time. This is rec- tified after a few minutes of driving, and the tire
pressures are displayed for the correct posi-
tions.
Restarting the tire pressure monitor
When you restart the tire pressure monitor, all
existing warning messages are deleted and the
h warning lamp goes out. The monitor uses
the currently set tire pressures as the reference
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 set ref-
erence values manually as described here. The
tire pressure monitor then monitors the new tire
pressure values.
XSet the tire pressure to the value recommen-ded for the corresponding driving situation on
the Tire and Loading Information placard on
the B-pillar on the driver's side.
You can find more tire pressures for various
operating conditions in the tire pressure table
inside the filler flap.
Observe the information on tire pressure
when doing so (
Ypage 260).
XMake sure that the tire pressure is correct on
all four wheels.
XEnsure that the SmartKey is in position 2in
the ignition lock.
XPress the =or; button on the steering
wheel to select the Serv.menu.
XPress the9or: button to select
Tire Pressure.
XPress the abutton.
The multifunction display shows the current
tire pressure for each tire or the Tire pres‐
surewillbedisplayedafterdrivinga few minutesmessage appears.
XPress the:button.
The UseCurrentPressuresasNewRef‐erenceValuesmessage appears in the mul-
tifunction display.
If you wish to confirm the restart:
XPress the abutton.
The TirePress.MonitorRestartedmes-
sage appears in the multifunction display.
After driving for a few minutes, the system
checks whether the current tire pressures are within the specified range. The new tire pres-
sures are then accepted as reference values
and monitored.
If you wish to cancel the restart:
XPress the %button.
The tire pressure values stored at the last
restart will continue to be monitored.
Tire pressure265
Wheels and tires
Z

PSI (pounds per square inch)
A standard unit of measure for tire pressure.
Aspect ratio
Relationship between tire height and tire width
in percent.
Tire pressure
This is pressure inside the tire applying an out-
ward force to each square inch of the tire's sur-
face. The tire pressure is specified in pounds per
square inch (psi), in kilopascals (kPa) or in bar.
The tire pressure should only be corrected when
the tires are cold.
Cold tire pressure
The tires are cold:
Rif the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and
Rif the vehicle has not been driven further than
1 mile (1.6 km)
Tread
The part of the tire that comes into contact with
the road.
Bead
The tire bead ensures that the tire sits securely
on the wheel. There are several steel wires in the
bead to prevent the tire from coming loose fromthe wheel rim.
Sidewall
The part of the tire between the tread and the
bead.
Weight of optional extras
The combined weight of those optional extras
that weigh more than the replaced standard
parts and more than 2.3 kg (5 lbs). These
optional extras, such as high-performance
brakes, level control, a roof rack or a high-per-
formance battery, are not included in the curb
weight and the weight of the accessories.
TIN (Tire Identification Number)
This is a unique identifier which can be used by
a tire manufacturer to identify tires, for example
for a product recall, and thus identify the pur-
chasers. The TIN is made up of the manufactur-
er's identity code, tire size, tire type code and
the manufacturing date.
Load bearing index
The load bearing index (also load index) is a code
that contains the maximum load bearing capa-
city of a tire.
Traction
Traction is the result of friction between the tires
and the road surface.
TWR (Tongue Weight Rating)
The TWR specifies the maximum permissible
weight that the ball coupling of the trailer tow
hitch can support.
Treadwear indicators
Narrow bars (tread wear bars) that are distrib-
uted over the tire tread. If the tire tread is level
with the bars, the wear limit of áin (1.6 mm)
has been reached.
Occupant distribution
The distribution of occupants in a vehicle at their
designated seating positions.
Total load limit
Nominal load and luggage load plus 68 kg
(150 lbs) multiplied by the number of seats in
the vehicle.
Changing a wheel
Flat tire
You can find information on what to do in the
event of a flat tire in the "Breakdown assistance"
section (
Ypage 246).
Rotating the wheels
GWARNING
Interchanging the front and rear wheels may
severely impair the driving characteristics if
the wheels or tires have different dimensions. The wheel brakes or suspension components
may also be damaged. There is a risk of acci-
dent.
Rotate front and rear wheels only if the wheels and tires are of the same dimensions.
Changing a wheel275
Wheels and tires
Z

!On vehicles equipped with a tire pressure
monitor, electronic components are located
in the wheel.
Tire-mounting tools should not be used near
the valve. This could damage the electronic
components.
Only have tires changed at a qualified spe-
cialist workshop.
Always observe the instructions and safety
notes under "Installing a wheel" (
Ypage 276).
The wear patterns on the front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before a clear wear pattern
has formed on the tires. Front tires typically
wear more on the shoulders and the rear tires in the center.
On vehicles that have the same size front and
rear wheels, you can rotate the wheels accord-
ing to the intervals in the tire manufacturer's
warranty book in your vehicle documents. If no
warranty book is available, the tires should be
rotated every 3,000 to 6,000 miles (5,000 to
10,000 km). Depending on tire wear, this may
be required earlier. Do not change the direction
of wheel rotation.
Clean the contact surfaces of the wheel and the
brake disc thoroughly every time a wheel is rota-
ted. Check the tire pressure and reactivate the
tire pressure monitor if necessary (
Ypage 265).
Direction of rotation
Tires with a specified direction of rotation have
additional benefits, e.g. if there is a risk of hydro-
planing. You will only gain these benefits if the
correct direction of rotation is observed.
An arrow on the sidewall of the tire indicates its
correct direction of rotation.
You may mount the spare wheel against the
direction of rotation. Adhere to the time restric-
tion on use as well as the speed limitation speci-
fied on the spare wheel.
Storing wheels
Store tires that are not being used in a cool, dry
and preferably dark place. Protect the tires from
oil, grease, gasoline and diesel.
Mounting a wheel
Preparing the vehicle
GWARNING
When you remove the spare wheel from the
spare wheel bracket, the vehicle’s weight dis-
tribution changes. If the vehicle is already
raised, the jack could tip over. There is a risk
of injury.
Remove the spare wheel from the spare wheel
bracket before lifting the vehicle.
XStop the vehicle on solid, non-slippery and
level ground.
XApply the parking brake.
XBring the front wheels into the straight-ahead
position.
XShift the automatic transmission to position
j.
XSwitch off the engine.
XRemove the vehicle tools and jack from the
vehicle (Ypage 244).
XRemove the spare wheel from the spare wheel bracket (Ypage 245).
XSafeguard the vehicle against rolling away.
Securing the vehicle to prevent it from
rolling away
XPlace chocks or other suitable items under
the front and rear of the wheel that is diago-
nally opposite the wheel you wish to change.
Raising the vehicle
GWARNING
If you do not position the jack correctly at the
appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle.
!Only position the jack at the appropriate
jacking point of the vehicle. Otherwise, you
could damage the vehicle.
276Changing a wheel
Wheels and tires

Observe the following when raising the vehi-
cle:
RTo raise the vehicle, only use the vehicle-spe-
cific jack that has been tested and approved
by Mercedes-Benz. If used incorrectly, the
jack could tip over with the vehicle raised.
RThe jack is designed only to raise and hold the
vehicle for a short time while a wheel is being
changed. It must not be used for performing
maintenance work under the vehicle.
RAvoid changing the wheel on uphill and down-
hill slopes.
RBefore raising the vehicle, secure it from roll-
ing away by applying the parking brake and
inserting wheel chocks. Do not disengage the
parking brake while the vehicle is raised.
RThe jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a large,
flat, load-bearing underlay must be used. On a
slippery surface, a non-slip underlay must be
used, e.g. rubber mats.
RDo not use wooden blocks or similar objects
as a jack underlay. Otherwise, the jack will not
be able to achieve its load-bearing capacity
due to the restricted height.
RMake sure that the distance between the
underside of the tires and the ground does not
exceed 1.2 in (3 cm).
RDo not place your hands or feet under the
raised vehicle.
RDo not lie under the vehicle.
RDo not start the engine when the vehicle is
raised.
RDo not open or close a door when the vehicle is raised.
RMake sure that no persons are present in the
vehicle when the vehicle is raised.
XUsing lug wrench :, loosen the bolts on the
wheel you wish to change by about one full
turn. Do not unscrew the bolts completely.
XAssemble the pump lever for the jack from the vehicle tool kit.
XTurn lowering screw =on the jack clockwise
as far as it will go using notch ;on the pump
lever.
Pressure release screw =is closed.
iDo not turn pressure release screw =by
more than one to two revolutions. Otherwise,
hydraulic fluid could escape.
XPosition jack Avertically under the jacking
point of axle carrier tube ?.
Changing a wheel277
Wheels and tires
Z

Make sure that jackAis at the correct posi-
tion under axle carrier tube ?. The front or
rear axle must sit securely in the recess of
jack A.
XKeep pumping until axle carrier tube ?sits
securely in the recess of jack Aand the base
of the jack lies evenly on the ground.
Ensure that the jack is located vertically under
the jacking point.
XRaise the vehicle by pumping until the tire is
no more than 1.2 in (3 cm) off the ground.
Removing a wheel
!Do not place wheel bolts in sand or on a dirty
surface. The bolt and wheel hub threads could
otherwise be damaged when you screw them
in.
When mounting/removing wheels, and for as
long as the wheels are removed, avoid applying
any external force on the brake disks. This could impair the level of comfort when braking.
XUnscrew the wheel bolts.
XRemove the wheel.
Mounting a new wheel
GWARNING
Oiled or greased wheel bolts/wheel nuts and
damaged wheel bolt/wheel nut/wheel hub
threads can cause wheel bolts/wheel nuts to
come loose. As a result, you could lose a
wheel while driving. There is a risk of an acci-
dent.
Never oil or grease wheel bolts/wheel nuts. In
the event of damage to the threads, contact a
qualified specialist workshop immediately.
Have the damaged wheel bolts/wheel nuts or
hub threads replaced/renewed. Do not con-
tinue driving.
GWARNING
If you tighten the wheel bolts or wheel nuts
when the vehicle is raised, the jack could tip
over. There is a risk of injury.
Only tighten the wheel bolts or wheel nuts
when the vehicle is on the ground.
!To prevent damage to the paintwork, hold
the wheel securely against the wheel hub
while screwing in the first wheel bolt.
Always pay attention to the instructions and
safety notes in the "Changing a wheel" section
(
Ypage 275).
Only use wheel bolts that have been designed
for the wheel and the vehicle. For safety rea-
sons, Mercedes-Benz recommends that you
only use wheel bolts which have been approved
for Mercedes-Benz vehicles and the respective
wheel.
XClean the wheel and wheel hub contact sur-
faces.
XPlace the new wheel on the wheel hub and
push it on.
XTighten the wheel bolts until they are finger-
tight.
Lowering the vehicle
GWARNING
The wheels could work loose if the wheel nuts and bolts are not tightened to the specified
tightening torque. There is a risk of accident.
Have the tightening torque immediately
checked at a qualified specialist workshop
after a wheel is changed.
XSlowly open the pressure release screw on
the jack using the pump lever by approx-
imately one full turn and carefully lower the
vehicle (
Ypage 276).
XYou can put the jack aside.
XTighten the wheel bolts evenly in a crosswisepattern in the sequence indicated (: toA).
278Changing a wheel
Wheels and tires

The tightening torque must be96 lb-ft
(130 Nm).
XDismantle the pump lever.
XPush the jack piston back in and close the
drain plug.
XUse the nuts to secure the faulty wheel to the
spare wheel bracket (Ypage 245).
XStow the jack and the vehicle tools in the
vehicle again.
XCheck the tire pressure of the newly installed
wheel and adjust it if necessary.
Observe the recommended tire pressure
(
Ypage 260).
If you are driving with the emergency spare
wheel installed, the tire pressure monitor can-
not function reliably. Only restart the tire pres-
sure monitor when the defective wheel has been replaced with a new wheel.
All mounted wheels must be equipped with func-
tioning sensors for the tire pressure monitor.
Wheel and tire combinations
You can ask for information regarding permittedwheel/tire combinations at an authorized
Mercedes-Benz Center.
!For safety reasons, Mercedes-Benz recom-
mends that you only use tires, wheels and
accessories which have been specifically
approved by Mercedes-Benz for your vehicle.
These are specially adapted to the various
driving safety systems, such as ABS or ESP
®.
Only use tires, wheels and accessories tested
and recommended by Mercedes-Benz. Cer-
tain characteristics, such as handling, vehicle
noise emissions, fuel consumption, etc. may
otherwise be adversely affected. In addition,
other wheel sizes may cause the tires to rub
against the vehicle body and axle compo-
nents, when under load. This may result in
damage to the tire or to the vehicle.
Mercedes-Benz is not responsible for any
damage caused by using tires, wheels or
accessories different from those recommen-
ded.
Information on tires, wheels and permissible
combinations can be obtained at a qualified
specialist workshop.
!Retreaded tires are neither tested nor rec-
ommended by Mercedes-Benz, since previ- ous damage cannot always be detected on
retreaded tires. As a result, Mercedes-Benz
cannot guarantee vehicle safety if retreaded
tires are mounted. Do not mount used tires if
you have no information about their previous
usage.
The recommended pressures for various oper-
ating conditions can be found:
Ron the Tire and Loading Information placard
on the B-pillar on the driver's side
Rin the tire pressure table in the fuel filler flap
Observe the notes on recommended tire pres-
sures under various operating conditions
(
Ypage 260).
Check tire pressures regularly, and only when
the tires are cold. Comply with the maintenance
recommendations of the tire manufacturer in
the vehicle document wallet.
Notes on equipping the vehicle:
Ralways install tires of the same size on one
axle (left/right)
Ralways install the same type of tires on your
vehicle (summer tires, winter tires, all-
weather tires, all-terrain tires)
Spare wheel
If the tire and wheel dimensions of the spare
wheel differ from the wheel to be replaced, the
spare wheel is an emergency spare wheel.
GWARNING
Wheel and tire dimensions as well as the type of tire can vary between the spare wheel and
the wheel to be replaced. When the spare
wheel is mounted, driving characteristics may be severely affected. There is a risk of an acci-
dent.
In order to reduce risks:
Ryou should therefore adapt your driving
style and drive carefully.
Rnever mount more than one spare wheel
that differs from the wheel to be replaced.
Ronly use a spare wheel that differs from the
wheel to be replaced for a short time.
Spare wheel279
Wheels and tires
Z