Wheels and tiresVehicle features and options
This chapter describes all standard, country-
specific and optional features offered with the
series. It also describes features that are not
necessarily available in your car, e. g., due to
the selected options or country versions. This
also applies to safety-related functions and
systems. The respectively applicable country
provisions must be observed when using the
respective features and systems.
Tire inflation pressure Safety information
The tire characteristics and tire inflation pres‐
sure influence the following:▷The service life of the tires.▷Road safety.▷Driving comfort.
Checking the tire inflation pressure
WARNING
A tire with low or missing tire inflation
pressure impacts handling, such as steering
and braking response. There is risk of an acci‐
dent. Regularly check the tire inflation pres‐
sure, and correct it as needed, e.g. twice a
month and before a long trip.◀
Also check the tire inflation pressure of the
emergency wheel in the trunk regularly, and
correct it as needed.
Tires have a natural, consistent loss of tire in‐
flation pressure.
Tires heat up while driving, and the tire infla‐
tion pressure increases along with the tire's
temperature. The tire inflation pressure speci‐
fications relate to cold tires or tires with the
ambient temperature.
Only check the tire inflation pressure when the
tires are cold. This means after driving no more
than 1.25 miles/2 km or when the vehicle has
been parked for at least 2 hours.
The displays of inflation devices may under-
read by up to 0.1 bar, 2 psi.
For Flat Tire Monitor: after correcting the tire
inflation pressure, reinitialize the Flat Tire
Monitor.
For Tire Pressure Monitor: after correcting the
tire inflation pressure, reset the Tire Pressure
Monitor.
Tire inflation pressure specifications
The tire inflation pressure table, refer to
page 255, contains all tire inflation pressure
specifications for the specified tire sizes at the
ambient temperature. The tire inflation pres‐
sure values apply to tire sizes approved by the
manufacturer of the vehicle for the vehicle
type.
To identify the correct tire inflation pressure,
please note the following:▷Tire sizes of your vehicle.▷Maximum permitted driving speed.
Tire inflation pressures up to
100 mph/160 km/h
For speeds of up to 100 mph/160 km/h and for
optimum driving comfort, note the pressure
values in the tire inflation pressure table, refer
to page 255, and adjust as necessary.
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Rotating wheels between axlesDifferent wear patterns can occur on the frontand rear axles depending on individual driving
conditions. The tires can be rotated between
the axles to achieve even wear. A dealer’s
service center or another qualified service cen‐
ter or repair shop will be glad to answer addi‐
tional questions at any time. After rotating,
check the tire pressure and correct if needed.
Rotating the tires is not permissible on vehi‐
cles with different tire sizes or rim sizes on the
front and rear axles.
Storage
Store wheels and tires in a cool, dry place with
as little exposure to light as possible.
Always protect tires against all contact with oil,
grease and fuels.
Do not exceed the maximum tire inflation pres‐
sure indicated on the side wall of the tire.
Run-flat tires
Label
RSC label on the tire sidewall.
The wheels consist of tires that are self-sup‐
porting, to a limited degree, and possibly spe‐
cial rims.
The support of the sidewall allows the tire to
remain drivable to a restricted degree in the
event of a tire inflation pressure loss.
Follow the instructions for continued driving
with a flat tire.
Changing run-flat tires
For your own safety, only use run-flat tires. No
spare tire is available in the case of a flat tire. A
dealer’s service center or another qualified
service center or repair shop will be glad to an‐
swer additional questions at any time.
Repairing a flat tire Safety measures▷Park the vehicle as far away as possible
from passing traffic and on solid ground.▷Switch on the hazard warning system.▷Secure the vehicle against rolling away by
setting the parking brake.▷Turn the steering wheel until the front
wheels are in the straight-ahead position
and engage the steering wheel lock.▷Have all vehicle occupants get out of the
vehicle and ensure that they remain out‐
side the immediate area in a safe place,
such as behind a guardrail.▷If necessary, set up a warning triangle at an
appropriate distance.
Mobility System
The concept
With the Mobility System, minor tire damage
can be sealed quickly to enable continued
travel. To accomplish this, sealant is pumped
into the tires, which seals the damage from the
inside.
The compressor can be used to check the tire
inflation pressure.
Information
▷Follow the instructions on using the Mobi‐
lity System found on the compressor and
sealant container.Seite 260MobilityWheels and tires260
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▷Use of the Mobility System may be ineffec‐
tive if the tire puncture measures approx.
1/8 in/4 mm or more.▷Contact a dealer’s service center or an‐
other qualified service center or repair
shop if the tire cannot be made drivable.▷If possible, do not remove foreign bodies
that have penetrated the tire.▷Pull the speed limit sticker off the sealant
container and apply it to the steering
wheel.▷The use of a sealant can damage the TPM
wheel electronics. In this case, have the
electronics checked at the next opportu‐
nity and have them replaced if needed.
Storage
The mobility system is in the left storage com‐
partment of the cargo area.
Sealant container
▷Sealant container, arrow 1.▷Filling hose, arrow 2.
Observe use-by date on the sealant container.
Compressor1Bottle unlocking2Holder for bottle3Inflation pressure dial4Reduce inflation pressure5On/off switch6Compressor7Connector/cable for socket8Connection hose
Filling the tire with sealant
1.Shake the sealant container.Seite 261Wheels and tiresMobility261
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Snow chains
Fine-link snow chains The manufacturer of your vehicle recommends
use of fine-link snow chains. Certain types of
fine-link snow chains have been tested by the
manufacturer of the vehicle and recommended
as road-safe and suitable.
Information regarding suitable snow chains is
available from a dealer’s service center or an‐
other qualified service center or repair shop.
Use
Use only in pairs on the rear wheels, equipped
with the tires of the following size:▷245/50 R 18.▷245/45 R 19.
Follow the snow chain manufacturer's instruc‐
tions.
Make sure that the snow chains are always
sufficiently tight. Retighten as needed accord‐
ing to the chain manufacturer's instructions.
Do not initialize the Flat Tire Monitor after
mounting snow chains, as doing so may result
in incorrect readings.
Do not initialize the Tire Pressure Monitor after
mounting snow chains, as doing so may result
in incorrect readings.
When driving with snow chains, briefly activate
Dynamic Traction Control if needed.
Maximum speed with snow chains Do not exceed a speed of 30 mph/50 km/hwhen using snow chains.
Rear wheel steering during operation with snow chains
General information
In order to guarantee free running of the
wheels when operating with snow chains, the
rear wheel steering of the integral active steer‐
ing must be switched off when snow chains
are mounted. For this, it is possible to confirm
via iDrive that snow chains are mounted.
Information WARNING
When rear wheel steering is switched on
and snow chains are mounted, there can be
contact between snow chains and the chassis.
There is risk of accidents or risk of property
damage. With mounted snow chains, switch
off the rear wheel steering.◀
Switching off rear wheel steering With the setting that snow chains are
mounted, the rear wheel steering is switched
off.
About iDrive:1."My Vehicle"2."Vehicle settings"3."Tire chains"4."Tire chains installed"
Starting with the permissible maximum speed
with snow chains of 30 mph/50 km/h the rear
wheel steering will be switched on automati‐
cally.
Tire Pressure Monitor TPM
The concept
The system monitors tire inflation pressure in
the four mounted tires. The system warns you
if there is a loss of pressure in one or more
tires. For this purpose, sensors in the tire
valves measure the tire inflation pressure and
tire temperature.
Information
With use of the system observe further infor‐
mation found under Tire inflation pressure, re‐
fer to page 254.
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▷The system has detected a wheel change,
but no reset was done.▷No reset was performed for the system.
The system therefore issues a warning
based on the tire inflation pressures before
the last reset.▷Inflation was not carried out according to
specifications.▷The tire inflation pressure has fallen below
the level of the last reset.
In these cases:
1.Check the tire pressure and correct as
needed.2.Reset the system.
Message in case of low tire pressure
The yellow warning lamp lights up.
A Check Control message is displayed.
▷There is a tire inflation pressure loss.▷No reset was performed for the system.
The system therefore issues a warning
based on the tire inflation pressures before
the last reset.
In these cases:
1.Reduce your speed and drive moderately.
Do not exceed a speed of
80 mph/130 km/h.2.At the next opportunity, e.g. gas station,
check and if necessary correct the tire in‐
flation pressure in all four tires.3.Reset the system.
Message in case of sharp tire inflation pressure loss
The yellow warning lamp lights up.
A symbol with the affected tires will be dis‐
played in the Check Control message.▷There is a flat tire or a major loss in tire in‐
flation pressure.▷No reset was performed for the system.
The system therefore issues a warning
based on the tire inflation pressures before
the last reset.
In these cases:
1.Reduce your speed and stop cautiously.
Avoid sudden braking and steering maneu‐
vers.2.Check whether the vehicle is fitted with
normal tires or run-flat tires.
Run-flat tires, refer to page 260, are la‐
beled with a circular symbol containing the
letters RSC marked on the tire's sidewall.
WARNING
A damaged regular tire with low or miss‐
ing tire inflation pressure impacts handling,
such as steering and braking response. Run-
flat tires can maintain limited stability. There is
risk of an accident. Do not continue driving if
the vehicle is not equipped with run-flat tires.
Observe the information on run-flat tires and
continued driving with these tires.◀
A low tire inflation pressure might turn on DSC
Dynamic Stability Control.
Actions in the event of a flat tire
Normal tires
1.Identify the damaged tire.
Do this by checking the air pressure in all
four tires.
The tire pressure gauge of the Mobility
System, refer to page 260, can be used for
this purpose.
If the tire inflation pressure in all four tires
is shown to be correct, it is possible that
the Tire Pressure Monitor did not perform
a reset. Then perform the reset.Seite 266MobilityWheels and tires266
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If identification of flat tire damage is not
possible, please contact a dealer’s service
center or another qualified service center
or repair shop.2.Fixing a flat tire, where applicable with the
Mobility System.3.Replacing a damaged tire, where applica‐
ble with the emergency wheel.
Use of sealant, e.g., the Mobility System, may
damage the TPM wheel electronics. In this
case, have the electronics checked at the next
opportunity and have them replaced if needed.
Run-flat tires Maximum speed
You may continue driving with a damaged tire
at speeds up to 50 mph/80 km/h.
Continued driving with a flat tire
If continuing to drive with a damaged tire:
1.Avoid sudden braking and steering maneu‐
vers.2.Do not exceed a speed of 50 mph/80 km/h.3.Check the air pressure in all four tires at
the next opportunity.
If the tire inflation pressure in all four tires
is shown to be correct, it is possible that
the Tire Pressure Monitor did not perform
a reset. In that case, carry out a reset.
Possible driving distance with complete loss of
tire inflation pressure:
The possible driving distance after a loss of tire
inflation pressure depends on cargo load, driv‐
ing style and road conditions.
A vehicle with an average load has a possible
driving range of approx. 50 miles/80 km.
A vehicle with a damaged tire reacts differ‐
ently, e.g., it has reduced lane stability during
braking, a longer braking distance and different
self-steering properties. Adjust your driving
style accordingly. Avoid abrupt steering ma‐
neuvers or driving over obstacles, e.g., curbs,
potholes, etc.
Because the possible driving distance de‐
pends on how the vehicle is used during the
trip, the actual distance may be shorter or lon‐
ger depending on the driving speed, road con‐
ditions, external temperature, cargo load, etc.
WARNING
Your vehicle handles differently when a
run-flat tire is damaged and has low or missing
tire inflation pressure, e.g., your lane stability is
reduced when braking, braking distances are
longer and the self-steering properties will
change. There is risk of an accident.
Drive moderately and do not exceed a speed of
50 mph/80 km/h.◀
System limits
The system does not function properly if a re‐
set has not been carried out, e.g., a flat tire is
reported though tire inflation pressures are
correct.
The tire inflation pressure depends on the
tire's temperature. Driving or exposure to the
sun will increase the tire's temperature, thus
increasing the tire inflation pressure. The tire
inflation pressure is reduced when the tire
temperature falls again. These circumstances
may cause a warning when temperatures fall
very sharply.
The system cannot indicate sudden serious
tire damage caused by external circumstances.
Malfunction The yellow warning lamp flashes andthen lights up continuously. A Check
Control message is displayed. No flat
tire or loss of tire inflation pressure can be de‐
tected.
Examples and recommendations in the follow‐
ing situations:▷A wheel without TPM electronics is
mounted, e.g. emergency wheel: Have itSeite 267Wheels and tiresMobility267
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Status displayThe current status of the flat tire monitor can
be displayed, e.g., whether the RPA is active.
About iDrive:1."My Vehicle"2."Vehicle status"3. "Flat Tire Monitor"
The status is displayed.
Initialization
When initializing the once set inflation tire
pressures serve as reference values in order to
detect a flat tire. Initialization is started by con‐
firming the tire inflation pressures.
Do not initialize the system when driving with
snow chains.
About iDrive:
1."My Vehicle"2."Vehicle status"3.Flat Tire Monitor reset4.Start the engine - do not drive off.5.Start the initialization: "Perform reset"6.Drive away.
The initialization is completed while driving,
which can be interrupted at any time.
The initialization automatically continues when
driving resumes.
Indication of a flat tire The yellow warning lamp lights up. A
Check Control message is displayed.
There is a flat tire or a major loss in tire
inflation pressure.
1.Reduce your speed and stop cautiously.
Avoid sudden braking and steering maneu‐
vers.2.Check whether the vehicle is fitted with
normal tires or run-flat tires.Run-flat tires, refer to page 260, are la‐
beled with a circular symbol containing the
letters RSC marked on the tire's sidewall.
WARNING
A damaged regular tire with low or miss‐
ing tire inflation pressure impacts handling,
such as steering and braking response. Run-
flat tires can maintain limited stability. There is
risk of an accident. Do not continue driving if
the vehicle is not equipped with run-flat tires.
Observe the information on run-flat tires and
continued driving with these tires.◀
When a flat tire is indicated, DSC Dynamic Sta‐
bility Control is switched on if needed.
System limits
A natural, even tire inflation pressure loss in all four tires will not be recognized. Therefore,
check the tire inflation pressure regularly.
Sudden serious tire damage caused by exter‐
nal circumstances cannot be recognized in ad‐
vance.
The system could be delayed or malfunction in
the following situations:
▷When the system has not been initialized.▷When driving on a snowy or slippery road
surface.▷Sporty driving style: spinning traction
wheels, high lateral acceleration (drifting).▷When driving with snow chains.
Actions in the event of a flat tire
Normal tires
1.Identify the damaged tire.
Do this by checking the air pressure in all
four tires.
The tire pressure gauge of the Mobility
System, refer to page 260, can be used for
this purpose.
If the tire inflation pressure in all four tires
is correct, the Flat Tire Monitor may notSeite 269Wheels and tiresMobility269
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have been initialized. In this case, initialize
the system.
If identification of flat tire damage is not
possible, please contact a dealer’s service
center or another qualified service center
or repair shop.2.Fix the flat tire using the Mobility System,
refer to page 260.
Run-flat tires
Maximum speed
You may continue driving with a damaged tire
at speeds up to 50 mph/80 km/h.
Continued driving with a flat tire
If continuing to drive with a damaged tire:
1.Avoid sudden braking and steering maneu‐
vers.2.Do not exceed a speed of 50 mph/80 km/h.3.Check the air pressure in all four tires at
the next opportunity.
If the tire inflation pressure in all four tires
is correct, the Flat Tire Monitor may not
have been initialized. In this case, initialize
the system.
Possible driving distance with complete loss of
tire inflation pressure:
The possible driving distance after a loss of tire
inflation pressure depends on cargo load, driv‐
ing style and road conditions.
A vehicle with an average load has a possible
driving range of approx. 50 miles/80 km.
A vehicle with a damaged tire reacts differ‐
ently, e.g., it has reduced lane stability during
braking, a longer braking distance and different
self-steering properties. Adjust your driving
style accordingly. Avoid abrupt steering ma‐
neuvers or driving over obstacles, e.g., curbs,
potholes, etc.
Because the possible driving distance de‐
pends on how the vehicle is used during the
trip, the actual distance may be shorter or lon‐
ger depending on the driving speed, road con‐
ditions, external temperature, cargo load, etc.
WARNING
Your vehicle handles differently when a
run-flat tire is damaged and has low or missing
tire inflation pressure, e.g., your lane stability is
reduced when braking, braking distances are
longer and the self-steering properties will
change. There is risk of an accident.
Drive moderately and do not exceed a speed of
50 mph/80 km/h.◀
Final tire failure
Vibrations or loud noises while driving can indi‐
cate the final failure of a tire.
Reduce speed and stop; otherwise, pieces of
the tire could come loose and cause an acci‐
dent.
Do not continue driving. Contact a dealer’s
service center or another qualified service cen‐
ter or repair shop.Seite 270MobilityWheels and tires270
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