272 OperationTires and wheelsThe TPMS only functions on wheels that
are equipped with the proper electronic
sensors. It monitors the tire inflation pres-
sure, as selected by the driver, in all four
tires. A warning is issued to alert you to a
decrease in pressure in one or more of the
tires.
Tire pressure inquiries are made using the
multifunction display. The present inflation
pressures are displayed only after a few
minutes’ travel time.
Switch on the ignition (
page 40).
Press buttonj or k on the mul-
tifunction steering wheel until the cur-
rent inflation pressures for each tire
appear in the multifunction display.
i
Possible differences between the readings
of a tire pressure gauge of an air hose, e.g. gas
station equipment, and the vehicle’s control
system can occur. Usually the readings issued by
the control system are more precise.
i
When the vehicle has been parked for longer
than 20 minutes, the message
Tire pressure
displayed after driving for a few
minutes.
appears in the multifunction display.
Warning!
G
It is the driver’s responsibility to calibrate
the TPMS on the recommended cold infla-
tion pressure. Underinflated tires affect the
ability to steer or brake the vehicle. You
might lose control over the vehicle.i
With a spare wheel mounted, the system
may still indicate the tire inflation pressure of the
removed road wheel for some minutes. If this
happens, keep in mind that the indicated value
where the spare wheel is mounted does not re-
flect the actual spare tire inflation pressure.
Warning!
G
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to
the Tire and Loading Information placard on
the driver’s door B-pillar or, if available, the
supplemental tire inflation pressure infor-
mation on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by care-
fully applying the brakes and avoiding
abrupt steering maneuvers.
273 Operation
Tires and wheels
Warning!
G
Each tire, including the spare (if provided),
should be checked every other week when
cold and inflated to the inflation pressure
recommended by the vehicle manufacturer
on the Tire and Loading Information placard
or the tire inflation pressure label. If your ve-
hicle has tires of a different size than the
size indicated on the Tire and Loading Infor-
mation placard or the tire inflation pressure
label, you should determine the proper tire
inflation pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires are significantly underinflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible, and inflate them to
the proper pressure. Driving on a significant-
ly underinflated tire causes the tire to over-
heat and can lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehi-
cle’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 com-
bined 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 continue
upon subsequent vehicle start-ups 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 intend-
ed. TPMS malfunctions may occur for a vari-
ety of reasons, including the installation of
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
If a condition causing the TPMS to malfunc-
tion develops, it may take up to 10 minutes for
the system to signal a malfunction using the
TPMS telltale flashing and illumination se-
quence.
The telltale extinguishes after a few minutes driv-
ing if the malfunction has been corrected.
i
Operating radio transmission equipment
(e.g. wireless headsets, two-way radios) in or
near the vehicle could cause the TPMS to mal-
function.
274 OperationTires and wheelsTire inflation pressure warnings
If the system detects a significant loss of
tire inflation pressure in one or more than
one tire, a message appears in the multi-
function display.Example illustrationThe respective tire is indicated by a red
rectangle. In addition, a warning signal
sounds.Restarting Advanced TPMS
The TPMS usually recognizes new refer-
ence values automatically, for example
when you have
adjusted the tire inflation pressure
changed wheels or tires
mounted new wheels or tires
If you want to set new reference values
manually:
Using the Tire and Loading Information
placard on the driver’s door B-pillar
(page 263) or, if available, the sup-
plemental tire inflation pressure
information on the inside of the fuel filler flap (
page 247), make sure the
tire inflation pressure of all four tires is
correct.
Press buttonè orÿ on the mul-
tifunction steering wheel repeatedly
until the standard display menu
appears in the multifunction display
(page 122).
Warning!
G
It is the driver’s responsibility to calibrate
the TPMS on the recommended cold infla-
tion pressure. Underinflated tires affect the
ability to steer or brake the vehicle. You
might lose control over the vehicle.
i
Restart the TPMS after adjusting the tire in-
flation pressure to the inflation pressure recom-
mended for the vehicle operating condition. Tire
pressure should only be adjusted on cold tires.
Observe the recommended tire inflation pres-
sure on the Tire and Loading Information placard
on the driver’s door B-pillar (
page 263). Some
vehicles may have supplemental tire inflation
pressure information for driving at high speeds
(
page 247) or for vehicle loads less than the
maximum loaded vehicle condition
(page 247). If such information is provided, it
can be found on the inside of the fuel filler flap.
275 Operation
Tires and wheels
Press buttonj or k repeatedly
until the current inflation pressures for
each tire appear in the display or the
following message appears in the dis-
playTire pressure
displayed after
driving for
a few minutes
Press the reset button (
page 114).
The following message will appear in
the multifunction display:
Restart tire
pressure monitor?
Press the æbutton.
The following message will appear in
the multifunction display:Tire Pressure Monitor
RestartedAfter driving a few minutes the system
verifies that the current tire inflation
pressures are within the system’s
specified range. Afterwards the current
tire inflation pressures are accepted as
reference pressures and then moni-
tored.
If you wish to cancel activation:
Press the çbutton.Potential problems associated with
underinflated and overinflated tires
Underinflated tires
Underinflated tires can:
cause excessive and uneven tire wear
adversely affect fuel economy
lead to tire failure from being
overheated
adversely affect handling
characteristicsWarning!
G
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.
276 OperationTires and wheelsOverinflated tires
Overinflated tires can:
adversely affect handling
characteristics
cause uneven tire wear
be more prone to damage from road
hazards
adversely affect ride comfort
increase stopping distance
Tire labeling
Besides tire name (sales designation) and
manufacturer name, a number of markings
can be found on a tire.
Following are some explanations for the
markings on your vehicle’s tires:1Uniform Quality Grading Standards
(
page 284)
2DOT, Tire Identification Number (TIN)
(page 281)
3Maximum tire load (
page 282)
4Maximum tire inflation pressure
(
page 283)
5Manufacturer
6Tire ply material (
page 286)
7Tire size designation, load and speed
rating (
page 277)
8Load identification (
page 280)
9Tire name
Warning!
G
Follow recommended tire inflation
pressures.
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.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
For more information, see “Rims and tires”
(
page 385).
278 OperationTires and wheelsRim diameter
The rim diameter4 (
page 277) is the
diameter of the bead seat, not the
diameter of the rim edge. Rim diameter is
indicated in inches (in).
Tire load rating
The tire load rating5 (page 277) is a
numerical code associated with the
maximum load a tire can support.
For example, a load rating of 91 corre-
sponds to a maximum load of 1356 lb
(615 kg) the tire is designed to support.
See also “Maximum tire load”
(
page 282) where the maximum load as-
sociated with the load index is indicated in
kilograms and lb.For additional information on tire load
rating, see “Load identification”
(
page 280).
Warning!
G
The tire load rating must always be at least
half of the GAWR (
page 287) of your
vehicle. Otherwise tire failure may be the re-
sult which may cause an accident and/or
serious injury to you or others.
Always replace rims and tires with the same
designation, manufacturer and type as
shown on the original part.
Warning!
G
Do not overload the tires by exceeding the
specified load limit or vehicle capacity
weight as indicated on the Tire and Loading
Information placard located on the driver’s
door B-pillar. Overloading the tires can over-
heat them, possibly causing a blowout.
Overloading the tires can also result in han-
dling or steering problems, or brake failure.
i
Tire load rating5 (
page 277) and tire
speed rating6 (
page 277) are also referred
to as “service description”.
279 Operation
Tires and wheels
Tire speed rating
The tire speed rating6 (
page 277)
indicates the approved maximum speed
for the tire.Summer tires
At the tire manufacturer’s option, any
tire with a speed capability above
149 mph (240 km/h) can include a
“ZR” in the size designation (for exam-
ple: 245/40 ZR18). To determine the
maximum speed capability of the tire,
the service description for the tire must
be referred to. The service description is comprised of the tire load rating5
(
page 277) and the tire speed
rating6 (
page 277).
If your tire includes “ZR” in the size
designation and no service
description5 and6 (
page 277) is
given, the tire manufacturer must be
consulted for the maximum speed
capability.
If a service description5 and6
(
page 277) is given, the speed capa-
bility is limited by the speed symbol in
the service description.
Example: 245/40 ZR18 97Y.
In this example, “97Y” is the service
description. The letter “Y” designates
the speed rating and the speed capabil-
ity of the tire is limited to 186 mph
(300 km/h).
Warning!
G
Even when permitted by law, never operate
a vehicle at speeds greater than the
maximum speed rating of the tires.
Exceeding the maximum speed for which
tires are rated can lead to sudden tire
failure, causing loss of vehicle control and
possibly resulting in an accident and/or
personal injury and possible death, for you
and for others.i
Tire load rating5 (
page 277) and tire
speed rating6 (
page 277) are also referred
to as “service description”.
Index
Speed rating
Q
up to 100 mph (160 km/h)
R
up to 106 mph (170 km/h)
S
up to 112 mph (180 km/h)
T
up to 118 mph (190 km/h)
H
up to 130 mph (210 km/h)
V
up to 149 mph (240 km/h)
W
up to 168 mph (270 km/h)
Y
up to 186 mph (300 km/h)
(Y)
above 186 mph (300 km/h)
ZR
above 149 mph (240 km/h)
283 Operation
Tires and wheels
For more information on tire load rating
(page 278).
For information on calculating total and
cargo load capacities (
page 264).
Maximum tire inflation pressure
1Maximum permissible tire inflation
pressure
This is the maximum permissible tire
inflation pressure for the tire.Always follow the recommended tire
inflation pressure (
page 268) for proper
tire inflation.
Warning!
G
Do not overload the tires by exceeding the
specified load limit or vehicle capacity
weight as indicated on the Tire and Loading
Information placard located on the driver’s
door B-pillar. Overloading the tires can over-
heat them, possibly causing a blowout.
Overloading the tires can also result in han-
dling or steering problems, or brake failure.
i
For illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
Warning!
G
Never exceed the max. tire inflation
pressure. 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.