brakes MERCEDES-BENZ C-CLASS CABRIOLET 2018 Owner's Guide

Parking Pilot no longer supports you with steer-
ing interventions and brake applications. When
Parking Pilot is finished, you must steer and
brake again yourself. Parking Assist
PARKTRONIC is still available.
Parking tips:
RThe way your vehicle is positioned in the park-
ing space after parking is dependent on vari-
ous factors. These include the position and
shape of the vehicles parked in front and
behind it and the conditions of the location. It
may be the case that Parking Pilot guides you
too far into a parking space, or not far enough
into it. In some cases, it may also lead you
across or onto the curb. Cancel the parking
procedure with Parking Pilot if necessary.
RYou can also prematurely select transmission
positionh. The vehicle redirects and does
not drive as far into the parking space. Should
the transmission change take place too early, the parking procedure is canceled. A sensible
parking position can no longer be achieved
from this position.
Exiting a parking space
In order for Parking Pilot to support you when
exiting the parking space:
Rthe border of the parking space must be high enough at the front and the rear. A curb is too
small, for example.
Rthe border of the parking space must not be
too wide. Your vehicle can be maneuvered
into a position at a maximum of 45° to the
starting position in the parking space.
Ra maneuvering distance of at least 3.3 ft
(1.0 m) must be available.
Parking Pilot can assist you with exiting a park-
ing space only if you have parked the vehicle
parallel to the direction of travel using the Park-
ing Pilot.
iIf Parking Assist PARKTRONIC detects
obstacles, Parking Pilot brakes automatically
whilst the vehicle is exiting the parking space.
You are responsible for braking in good time.
XStart the engine.
XRelease the electric parking brake.
XSwitch on the turn signal in the direction you
are pulling away.
XShift the transmission to position hork.
The Start Parking Pilot?Yes: OKNo:% message appears on the multifunction
display.
XTo cancel the procedure: press the%
button on the multifunction steering wheel or pull away.
or
XTo exit a parking space using Parking
Pilot: press the abutton on the multi-
function steering wheel.
The Parking Pilot Active Accelerate
and BrakeObserve Surroundingsmes-
sage appears on the multifunction display.
XLet go of the multifunction steering wheel.
XPull away, being ready to brake at all times. Do
not exceed a maximum speed of approx-
imately 6 mph (10 km/h) when exiting a park-
ing space. Otherwise, Parking Pilot is can-
celed immediately.
XDepending on the message or as required,
shift the transmission to position hork.
Parking Pilot immediately steers in the other
direction. The Parking Pilot Active
Accelerate and BrakeObserve Sur‐roundingsmessage appears on the multi-
function display.
iYou will achieve the best results by waiting
for the steering procedure to complete before
pulling away.
If you back up after activation, the steering
wheel is moved to the straight-ahead posi-
tion.
XDrive forwards and reverse as prompted by
the Parking Assist PARKTRONIC warning dis-
plays, several times if necessary.
Once you have exited the parking space com-
pletely, the steering wheel is moved to the
straight-ahead position. You hear a tone and the
Parking Pilot Finished
message appears
on the multifunction display. You will then have
to steer and merge into traffic on your own.
Parking Assist PARKTRONIC is still available.
You can take over the steering before the vehi-
cle has exited the parking space completely.
This is useful if you recognize that it is already
possible to pull out of the parking space.
Driving systems169
Driving and parking
Z

Canceling Active Parking Pilot
XStop the movement of the multifunction
steering wheel or steer yourself.
Parking Pilot is canceled immediately. The
Parking
PilotCanceledmessage appears
on the multifunction display.
or
XPress the Parking Assist PARKTRONIC button
(Ypage 172).
Parking Assist PARKTRONIC is switched off
and Parking Pilot is immediately canceled.
The Parking Pilot Canceled
message
appears on the multifunction display.
Parking Pilot is canceled automatically when:
Rthe electric parking brake is engaged
Rtransmission position jis selected
Rparking using Parking Pilot is no longer pos-
sible
Ryou are driving faster than 6 mph (10 km/h)
Ra wheel spins, ESP®intervenes or fails. In
such cases the ÷warning lamp lights up in
the instrument cluster
A warning tone sounds. The parking symbol dis-
appears and the multifunction display shows the
Parking Pilot Canceled
message.
When Parking Pilot is canceled, you must steer
and brake again yourself.
If a system malfunction occurs, the vehicle is
braked to a standstill. To drive on, depress the
accelerator again.
Parking Assist PARKTRONIC
Important safety notes
Parking Assist PARKTRONIC is an electronic
parking aid with ultrasound. It monitors the area
around your vehicle using six sensors in the
front bumper and six sensors in the rear
bumper. Parking Assist PARKTRONIC visually
and audibly indicates the distance between your
vehicle and an object.
Parking Assist PARKTRONIC is only an aid. It is
not a replacement for your attention to your
immediate surroundings. You are always
responsible for safe maneuvering, parking and
exiting a parking space. Make sure that there
are no persons, animals or objects in the maneu- vering area while maneuvering and parking in/
leaving parking spaces.
!When parking, pay particular attention to
objects above or below the sensors, such as
flower pots or trailer drawbars. Parking Assist PARKTRONIC does not detect such objects
when they are in the immediate vicinity of the
vehicle. You could damage the vehicle or the
objects.
The sensors may not detect snow and other
objects that absorb ultrasonic waves.
Ultrasonic sources such as an automatic car
wash, the compressed-air brakes of a truck or
a pneumatic drill could cause Parking Assist
PARKTRONIC to malfunction.
Parking Assist PARKTRONIC may not function
correctly on uneven terrain.
Parking Assist PARKTRONIC is activated auto-
matically when you:
Rswitch on the ignition
Rshift the transmission to position h,k or
i
Parking Assist PARKTRONIC is deactivated at
speeds above 11 mph (18 km/h). It is reactiva-
ted at lower speeds.
Range of the sensors
Parking Assist PARKTRONIC does not take into
account obstacles located:
Rbelow the detection range, e.g. people, ani-
mals or objects.
Rabove the detection range, e.g. overhanging
loads, tail sections or loading ramps of trucks.
:Sensors in the front bumper, left-hand side
(example)
170Driving systems
Driving and parking

Active Lane Keeping Assist
Generalnotes
Active Lan eKeepin gAssis tmonitors th earea in
fron tof your vehicl eby mean sof multifunction
camera :at th eto pof th ewindshield. Various
differen tareas to th efront, rear and side of your
vehicl eare also monitore dwit hth eaid of th e
radar sensor system. Active Lan eKeepin g
Assis tdetects lan emarking son th eroad and
can warn you before you leav eyour lan eunin-
tentionally. If you do no treac tto th ewarning , a
lane-correcting application of th ebrakes can
bring th evehicl ebac kint oth eoriginal lane.
This function is available in th erange between
40 mph and 12 0mph (60 km/h and 20 0km/h).
Important safety notes
If you fail to adapt your drivin gstyle, Active Lan e
Keepin gAssis tcan neither reduce th eris kof an
acciden tno roverride th elaws of physics .Active
Lan eKeepin gAssis tcanno ttak eaccoun tof
road and weather conditions. It may no trecog-
niz etraffic situations. Active Lan eKeepin g
Assis tis only an aid. You are responsibl efor th e
distanc eto th evehicl ein front, for vehicl e
speed, for braking in goo dtime and for stayin gin
your lane.
Active Lan eKeepin gAssis tcanno tcontinuously
keep your vehicl ein it slane.
GWARNIN G
Active Lan eKeepin gAssis tcanno talways
clearly detec tlan emarkings.
In suc hcases, Active Lan eKeepin gAssis t
can :
Rgivean unnecessary warning and then
mak e acourse-correcting brak eapplication
to th evehicl e
Rnotgiv e a warning or interven e
There is aris kof an accident.
Always pay particular attention to th etraffic
situation and keep within th elane, especially
if Active Lan eKeepin gAssis talerts you. Ter -
minate th eintervention in anon-critical driv-
ing situation .
The system may be impaire dor may no tfunction
if:
Rthere is poor visibility, e.g. due to insufficien t
illumination of th eroad ,or due to snow, rain ,
fog or spray
Rthere is glare, e.g. from oncomin gtraffic, th e
sun or reflection from other vehicles (e.g. if
th eroad surfac eis wet )
Rthewindshield is dirty, fogged up, damaged or
covered, for instance by asticker, in th evicin-
it y of th ecamera
Rth eradar sensor sin th efron tor rear bumpers
or th eradiato rtrim are dirty, e.g. obscured by
snow
Rthere are no ,several or unclear lan emarking s
for alane, e.g. in areas wit hroad construction
wor k
Rthelan emarking sare wor naway, dark or cov-
ere dup, e.g. by dir tor snow
Rth edistanc eto th evehicl ein fron tis to osmall
and th elan emarking sthus canno tbe detec -
te d
Rth elan emarking schang equickly, e.g. lanes
branch off ,cross on eanother or merge
Rth eroad is narrow and windin g
Rthere are highly variable shad econdition son
th eroadway
If no vehicl eis detecte din th eadjacent lan eand
broke nlan emarking sare detected, no lane-cor-
recting brak eapplication is made .
Warning vibration in th esteering wheel
A warning may be given if afron twhee lpasses
ove r alan emarking .It will warn you by mean sof
intermittent vibration in th esteering whee lfor
up to 1. 5seconds.
Driving systems189
Driving and parking
Z

Display messagesPossible causes/consequences andMSolutions
Phone No ServiceYour vehicleis outside th enetwork provider' stransmitter/receiver
range.
XWait until th emobile phone operational readiness symbol appear s
in th emultifunction display.
J
TrunkPartitionOpe n
The trunk partition is open .
XCloseth etrunk partition (Ypage 90).
K
While stationary,apply the brakesbefore operatingthe softtop .
The vehicl eis stationary and you tr yto open or close th esof ttop.
XDepress th ebrak epedal .
XPush or pull th esof tto pswitch again until th esof tto pis full yopen
or closed (Ypage 89).
K
Convertible TopOperation Possibleto 35 mph
If you drive at speeds of mor ethan 35 mph (60 km/h), you canno t
open or close th esof ttop.
XDo no tdrive at speeds abov e35 mph (60 km/h).
XFull yopen or close th esof tto p (Ypage 89) .
K
ConvertibleTopLow‐ering
The sof tto pis no tfully opened or closed .The hydraulic sare depres-
surized.
XFull yopen or close th esof tto p (Ypage 89).
K
Open/Clos eConver ‐tibleTopCompletel y
The roofis no tlocked.
If you drive at speeds of mor ethan 35 mph (60 km/h), you canno t
open or close th esof ttop.
XPull ove rand stop th evehicl esafely as soo nas possible, payin g
attention to roa dand traffic conditions.
XPush or pull and hold th esoft-to pswitch until th esof tto pis full y
open or closed (Ypage 89).
K
Start Engine SeeOperator'sManual
The on-boar dvoltag eis to olow.
XStart th eengine.
¥
Check Washer Fluid
The washer flui dlevel in th ewasher flui dreservoir has dropped belo w
th eminimum .
XAddwasher flui d (Ypage 285).
Display messages239
On-board computer and displays
Z

XPress9or: on the steering wheel to
select the Servicemenu and confirm with
a.
XPress 9or: on the steering wheel to
select the ASSYST PLUSsubmenu and con-
firm with a.
The service due date appears in the multi-
function display.
Information about Service
Resetting the ASSYST PLUS service
interval display
!If the ASSYST PLUS service interval display
has been inadvertently reset, this setting can
be corrected at a qualified specialist work-
shop.
Have service work carried out as described in
the Maintenance Booklet. This may otherwise
lead to increased wear and damage to the
major assemblies or the vehicle.
A qualified specialist workshop, e.g. an author-
ized Mercedes-Benz Center, will reset the
ASSYST PLUS service interval display after the
service work has been carried out. You can also
obtain further information on maintenance
work, for example.
Special service requirements
The specified maintenance interval takes only
the normal operation of the vehicle into
account. Under arduous operating conditions or
increased load on the vehicle, maintenance
work must be carried out more frequently, for
example:
Rregular city driving with frequent intermediate
stops
Rif the vehicle is primarily used to travel short
distances
Ruse in mountainous terrain or on poor road
surfaces
Rif the engine is often left idling for long periods
Under these or similar conditions, have, for
example, the air filter, engine oil and oil filter
replaced or changed more frequently. Under
arduous operating conditions, the tires must be
checked more often. Further information can be obtained at a qualified specialist workshop, e.g.
an authorized Mercedes-Benz Center.
Driving abroad
An extensive Mercedes-Benz Service network is
also available in other countries. You can obtain
further information from any authorized
Mercedes-Benz Center.
Care
General notes
!
For cleaning your vehicle, do not use any of
the following:
Rdry, rough or hard cloths
Rabrasive cleaning agents
Rsolvents
Rcleaning agents containing solvents
Do not scrub.
Do not touch the surfaces or protective films
with hard objects, e.g. a ring or ice scraper.
You could otherwise scratch or damage the
surfaces and protective film.
!Do not park your vehicle for a long period of
time directly after cleaning, particularly after
cleaning the wheel rim with wheel cleaner.
Wheel cleaner can lead to the increased cor-
rosion of the brake discs and pads. Therefore,
drive for a few minutes after cleaning. By
heating up the brakes, the brake discs and
pads dry. The vehicle can then be parked for a
long period of time.
HEnvironmental note
Dispose of empty packaging and cleaning
cloths in an environmentally responsible man-
ner.
Regular care of your vehicle is a condition for
retaining the quality in the long term.
Use care products and cleaning agents recom-
mended and approved by Mercedes-Benz.
Washing the vehicle and cleaning the
paintwork
Automatic car wash
GWARNING
Braking efficiency is reduced after washing
the vehicle. There is a risk of an accident.
286Care
Maintenance and care

After the vehicle has been washed, brake
carefully while paying attention to the traffic
conditions until full braking power is restored.
!When Active Brake Assist, Distance Pilot
DISTRONIC or the HOLD function is activated,
the vehicle brakes automatically in certain
situations.
To avoid damage to the vehicle, deactivate
these systems in the following or similar sit-
uations:
Rwhen towing the vehicle
Rin the car wash
!Preferably use automatic car washes with
adjustable high-pressure pre-cleaning. This
corresponds with the specification for the
Cabriolet program. In car washes that use
high water pressures, there is a risk that a
small amount of water may leak into the vehi-
cle.
!Make sure that the vehicle is not subse-
quently treated with hot wax.
!Always remove the SmartKey before wash-
ing the vehicle in a car wash. This ensures that the wind deflector on the windshield is retrac-
ted. The wind deflector may otherwise be
damaged.
!Never clean your vehicle in a Touchless
Automatic Car Wash as these use special
cleaning agents. These cleaning agents can
damage the paintwork or plastic parts.
!Make sure that:
Rthe side windows and soft top are closed
completely
Rthe blower is switched off
Rthe windshield wiper switch is in position 0
Rthe 360° camera or the rear view camera is
deactivated
The vehicle may otherwise be damaged.
!Make sure that the automatic transmission
is in neutral position iwhen washing your
vehicle in a tow-through car wash. The vehicle
may otherwise be damaged.
ROperating with the SmartKey:
Do not remove the SmartKey from the igni-
tion lock. Do not open the driver's door
when the engine is switched off or at very
low speeds. Otherwise, when in transmis- sion position
hork, the automatic
transmission will automatically switch to
park position jand block the wheels.
ROperating with the Start/Stop button:
Do not open the driver's door when the
engine is switched off or at very low
speeds. Otherwise, when in transmission
position hork, the automatic transmis-
sion will automatically switch to park posi-
tion jand block the wheels.
Observe the following to make sure that the
automatic transmission stays in neutral i:
Operating with the SmartKey and Start/Stop
button:
XMake sure that the ignition is switched on.
XMake sure that the vehicle is stationary.
XDepress and hold the brake pedal.
Operating with the Start/Stop button only:
XEngage park position j.
XRelease the brake pedal.
XRemove Start/Stop button from ignition lock
(Ypage 124).
XInsert the SmartKey into the ignition lock.
XSwitch on the ignition.
XDepress and hold the brake pedal.
Operating with the SmartKey and Start/Stop
button:
XEngage neutral i.
XRelease the brake pedal.
XRelease the electric parking brake, if neces-
sary.
XSwitch off the ignition and leave the SmartKey
in the ignition lock.
You can wash the vehicle in an automatic car
wash from the very start.
If the vehicle is very dirty, pre-wash it before
cleaning it in an automatic car wash.
After using an automatic car wash, wipe off wax
from the windshield and the wiper blades. This
will prevent smears and reduce wiping noises
caused by residue on the windshield.
Washing by hand
In some countries, washing by hand is only
allowed at specially equipped washing bays.
Observe the legal requirements in each country.
Care287
Maintenance and care
Z

and cleaning agents recommended and
approved by Mercedes-Benz.
Cleaning the wheels
GWARNING
The water jet from a circular jet nozzle (dirt
blasters) can cause invisible exterior damage
to the tires or chassis components. Compo-
nents damaged in this way may fail unexpect-
edly. There is a risk of an accident.
Do not use power washers with circular jet
nozzles to clean the vehicle. Have damaged
tires or chassis components replaced imme-
diately.
!Do not use acidic wheel cleaning products
to remove brake dust. This could damage
wheel bolts and brake components.
!Do not park your vehicle for a long period of
time directly after cleaning, particularly after
cleaning the wheel rim with wheel cleaner.
Wheel cleaner can lead to the increased cor-
rosion of the brake discs and pads. Therefore,
drive for a few minutes after cleaning. By
heating up the brakes, the brake discs and
pads dry. The vehicle can then be parked for a
long period of time.
Cleaning the windows
GWARNING
You could become trapped by the windshield wipers if they start moving while cleaning the
windshield or wiper blades. There is a risk of
injury.
Always switch off the windshield wipers and
the ignition before cleaning the windshield or
wiper blades.
!Do not use dry cloths, abrasive products,
solvents or cleaning agents containing sol-
vents to clean the inside of the windows. Do
not touch the insides of the windows with
hard objects, e.g. an ice scraper or ring. There
is otherwise a risk of damaging the windows.
!Clean the water drainage channels of the
windshield and the rear window at regular
intervals. Deposits such as leaves, petals and pollen may under certain circumstances pre- vent water from draining away. This can lead
to corrosion damage and damage to elec-
tronic components.
XClean the inside and outside of the windows
with a damp cloth and a cleaning product that
is recommended and approved by Mercedes-
Benz.
Cleaning wiper blades
GWARNING
You could become trapped by the windshield wipers if they start moving while cleaning the
windshield or wiper blades. There is a risk of
injury.
Always switch off the windshield wipers and
the ignition before cleaning the windshield or
wiper blades.
!Do not pull the wiper blade. Otherwise, the
wiper blade could be damaged.
!Do not clean wiper blades too often and do
not rub them too hard. Otherwise, the graph-
ite coating could be damaged. This could
cause wiper noise.
!Hold the wiper arm securely when folding
back. The windshield could be damaged if the
wiper arm smacks against it suddenly.
XFold the windshield wiper arms away from the
windshield (Ypage 112).
XCarefully clean the wiper blades with a damp
cloth.
XFold the windshield wiper arms back again
before switching on the ignition.
Cleaning the exterior lighting
!Only use cleaning agents or cleaning cloths
which are suitable for plastic light lenses.
Unsuitable cleaning agents or cleaning cloths
could scratch or damage the plastic light len- ses.
XClean the plastic lenses of the exterior light-
ing using a wet sponge and a mild cleaning
agent, e.g. Mercedes-Benz car shampoo or
cleaning cloths.
Care291
Maintenance and care
Z

XConnect positive terminal:on your veh icleto positive terminal ;of donor battery Cusing the
jumper cable, Always begin with positive terminal :on your own vehicle first.
XStart the engine of the donor veh icleand run itat idling speed.
XConnect negative terminal =of donor battery Cto earth point ?of your vehicle using the
jumper cable. beginning with donor battery Cfirst.
XStart the engine.
XBefore disconnecting the jumper cables, let the engine run for several minutes.
XFirst, remove the jumper cables from ground point? and negative terminal =, then from pos-
itive clamp :and positive terminal ;. Begineach time at the contacts on your own vehicle first.
XClose cover Aof positive terminal :after removing jumper cables.
XFold panel Bshut.
XHave the battery checked at a qualified specialist workshop.
Jump-starting isnot cons idered to bea normal operating condition.
iJumper cables and further information regarding jump-starting can be obtained at any qualified
specialist workshop.
Towing and tow-starting
Important safety notes
GWARNING
Functions relevant to safety are restricted or
no longer availab leif:
Rthe engine isnot running.
Rthe brake system or the power steering is
malfunctioning.
Rthere isa malfunction inthe voltage supply
or the veh icle's electrical system.
If your veh icle is bein g towed, much more
force may benecessary to steer or brake.
There isa risk of an acc ident.
In such cases, use a tow bar. Before to wing,
make sure that the steering moves freely.
GWAR NING
You can no longer steer the veh icle ifthe
steering wheel lock has been engaged. There
is a risk of an acc ident.
Alwa ysswit ch off the ignition when to wingthe
veh icle wit h a tow cable or a tow bar.
GWARNING
When to wingor tow-starting another vehicle
and its weight isgreater than the permissible
gross weight of your vehicle, the:
Rthe to wingeye could detach itself
Rthe vehicle /trailer combination could roll-
over.
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the per- missible gross weight of your vehicle.
Details on the permissible gross vehicle weight
of your vehicle can be found on the vehicle iden-
tification plate (
Ypage 339).
!When Active Brake Assist, Distance Pilot
DISTRONIC or the HOLD function is activated,
the vehicle brakes automatically in certain
situations.
To avoid damage to the vehicle, deactivate
these systems in the foll owing or similar sit-
uations:
Rwhen to wingthe vehicle
Rin the car wash
!Make sure that the electric parking brake is
released. Ifthe electric parking brake is faulty,
vis ita qualified specialist workshop.
!Secure the tow rope or tow bar to the to wing
eye only. Otherwise, the vehicle could
become damaged.
306Towing and tow-starting
Breakdown assistance

Important safety notes
GWARNING
If wheels and tires of th ewrong siz eare used,
th ewhee lbrakes or suspension component s
may be damaged. Ther eis aris kof an acci-
dent.
Always replace wheels and tires wit hthose
that fulfill th especification sof th eoriginal
part .
When replacing wheels, mak esur eto use th e
correct:
Rdesignation
Rmodel
When replacing tires ,mak esur eto use th e
correct:
Rdesignation
Rmanufacturer
Rmodel
GWARNIN G
A flat tire severely impairs th edriving ,steer -
ing and braking characteristics of th evehicle.
Ther eis aris kof accident.
Tires without run-flat characteristics :
Rdo notdriv ewit h a flat tire.
Rimmediately replace th eflat tire wit hyour
emergenc yspar ewhee lor spar ewheel, or
consult aqualified specialist workshop.
Tires wit hrun-flat characteristics :
Rpay attention to theinformation and warn -
ing notice son MOExtended tires (tire swit h
run-flat characteristics).
Accessories that are no tapprove dfor your vehi-
cle by Mercedes-Ben zor are no tbein gused cor-
rectl ycan impair th eoperating safety.
Before purchasing and usin gnon-approve d
accessories, visit aqualified specialist work-
sho pand inquire about :
Rsuitability
Rlegal stipulation s
Rfactory recommendation sFurther information regarding wheels and tires
can be foun
dunder "Wheel/tire combinations"
(
Ypage 336).
You can ask for information regarding permitte d
wheel-tire combination sat an authorize d
Mercedes-Ben zCenter.
Information on tire pressur ecan be found:
Ron th eTir eand Loading Information placard
on th eB-pillar on th edriver' sside
(
Ypage 322)
Rin th etire pressur etable in th efuel filler flap
(Ypage 315)
Runder "Tir epressure" (Ypage 315)
Operation
Information on driving
Checkth etire pressur ewhen th evehicl eis
heavily laden and adjust prio rto atrip.
While driving ,pay attention to vibrations, noises
and unusual handlin gcharacteristics ,e.g. pull-
ing to on eside .This may indicat ethat th e
wheels or tires are damaged. If you suspec tthat
a tire is defective, reduce your spee dimmedi-
ately. Stop th evehicl eas soo nas possible to
chec kth ewheels and tires for damage. Hidden
tire damag ecould also be causing th eunusual
handlin gcharacteristics .If you fin dno sign sof
damage, hav eth etires and wheels checke dat a
qualified specialist workshop.
When parking your vehicle, mak esur ethat th e
tires do no tget deformed by th ecur bor other
obstacles. If they canno tbe avoided, driv eove r
obstacles suc has curbs slowly and at an obtuse
angle. Otherwise, you may damag eth ewheels
or tires .
Notes on high performance tires
GWARNIN G
Due to th especial tire tread in combination
wit hth eoptimized rubber compound ,there is
an increased ris kof hydroplaning and skid-
din gon damp or wet road surfaces. In addi-
tion ,tire traction is significantly reduce dat
low outside temperatures and low tire-oper -
ating temperatures .Ther eis aris kof an acci-
dent.
312Operation
Wheels and tires

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 kilopascal (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 5 lbs (2.3 kg). 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.
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
The "Breakdown assistance" section
(Ypage 296) contains information and notes on
how to deal with a flat tire. Information on driv-
ing with MOExtended tires in the event of a flat
tire can be found under "MOExtended tires (tires
with run-flat characteristics" (
Ypage 297).
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.
!On vehicles equipped with a tire pressure
monitor, electronic components are located
in the wheel.
Changing a wheel331
Wheels and tires
Z