2018 MERCEDES-BENZ CLA warning

with run-flat characteristics) "s ection
( Y
page 271). R
Only moun tt ires of th ec orrec ts iz eo nt ot he
wheels. R
Break in new tires at moderat es peeds for the
firs t6 0m iles (10 0k m) .T he ne wt ires only
reac ht he ir full performanc ea fter this dis-
tance. R
Do not driv ew ith tires which have too little
tread depth, as this significantly reduces the
traction on wet roads (hydroplaning). R
Replace th et ires after six years at th el atest,
regardless of wear.
Observe th en otes on th ee mergency spare
wheel ( Y
page 312).
MOExtended tires (tires with run-flat
properties) With MOExtended tires (tires with run flat char-
acteristics) ,y ou can continue to driv ey our vehi-
cle even if there is at otal loss of pressure in one
or mor et ires.
MOExtended tires may only be used in conjunc-
tio nw ith an activated tir ep ressure loss warning
system (Canada only) or tir ep ressure monitor
(US Ao nly) and only on wheels specifically tes-
ted by Mercedes-Benz.
Notes on driving with MOExtended tires with a
flat tir e( Y
page 271).
Vehicles equipped with MOExtended tires are
not equipped with aT IREFIT kit at th ef actory. It
is therefore recommended that you additionally
equip your vehicle with aT IREFIT kit if you mount
tires that do not feature run-flat properties, e.g.
winter tires. AT IREFI Tk it may be obtained from
aq ualified specialist workshop.
Winter operation
General notes Have your vehicle winter-proofed at aq ualified
specialist workshop at th eo nset of winter.
Observe th en otes in th e" Changing aw heel"
sectio n( Y
page 307). Driving with summer tires At temperatures below 45 ‡( +7 †) ,s umme r
tire sl os ee las ti cit ya nd therefore traction and
braking power .C hange th et ires on your vehicle
to M+S tires. Usin gs ummer tires at ver yc old
temperatures coul dc aus ec ra ck stof orm,
thereb yd amaging th et ires permanently.
Mercedes-Ben zc anno ta ccept responsibilit yf or
this type of damage.
G WARNING
Damaged tires can caus et ir ei nflation pres-
sure loss .Asar esult, you coul dl ose control of
your vehicle .T her eisar isk of accident.
Chec kt he tires regularly for sign sofd amage
and replace any damage dt ires immediately.
M+S tires
G WARNING
M+S tires with at ir et re ad dept hofl ess than

When you have mounted the M+S tires: X
Check the tire pressures ( Y
page 290).X
Restart the tire pressure monitor (USA only)
( Y
page 297).X
Restart the tire pressure loss warning system
(Canada) ( Y
page 294)
Snow chains
G WARNING
If snow chains are mounted on the rear
wheels, the snow chains could cause abrasion
to the vehicle body or to chassis components.
This could cause damage to the vehicle or the
tires. There is ar isk of an accident.
To avoid hazardous situations: R
never mount snow chains on the rear
wheels R
only mount snow chains in pairs on the
fron tw heels.
! On some tire sizes there is not enough space
for snow chains. To avoid damage to the vehi-
cle or tires, observe the "Wheel and tire com-
binations" section under "Tires and wheels".
For safety reasons, Mercedes-Benz recom-
mends that you only use snow chains that have
been specially approved for your vehicle by
Mercedes-Benz ,ora re of ac orresponding
standard of quality. For more information,
please contact aq ualified specialist workshop.
If you inten dtom ount snow chains, please bear
the following points in mind: R
Sno wc hains may not be mounted on all
wheel/tire combinations. Permissible wheel-
tire combinations ( Y
page 312).R
Only use snow chains when driving on roads
completely covered by snow. Remove the
snow chains as soon as possible when you
come to ar oad that is not snow-covered.R
Local regulations may restrict the use of snow
chains. Observe the appropriate regulations if
you wish to mount snow chains. R
Do not exceed the maximum permissible
speed of 30 mph (50 km/h). R
Never use Parking Pilot when snow chains are
installed ( Y
page 165). You may wish to deactivat eE SP ®
when pulling
away with snow chains installed .Y ou can
thereby allow the wheels to spin in ac ontrolled
manner, achieving an increased driving force
(cutting action). R
Deactivate ESP ®
(all vehicles except
Mercedes-AMG vehicles) ( Y
page 65)R
Deactivate ESP ®
(Mercedes-AMG vehicles)
( Y
page 66)
Information about driving with an emergency
spare wheel ( Y
page 312).
Tir ep re ssure
Tir ep re ssure specifications
Important safety notes
G WARNING
Underinflated or overinflated tires pose the
following risks: R
the tires may burst, especially as the load
and vehicle speed increase. R
the tires may wear excessively and/or
unevenly, which may greatly impair tire
traction. R
the driving characteristics, as well as steer-
ing and braking, may be greatly impaired.
There is ar isk of an accident.
Follow recommended tire inflation pressures
and check the pressure of all the tires includ-
ing the spare wheel: R
monthly, at least R
if the load changes R
before beginnin gal ong journeyR
under differen to perating conditions, e.g.
off-road driving
If necessary, correct the tire pressure.
i The data on the Tire and Loading Informa-
tion placard and tire pressure table shown
here are examples. Tire pressure specifica-
tions 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 Infor-290
Tir ep re ssure
Wheels and tires

If the tire pressures have been set to the lower
values for lighter load sa nd/or lowe rr oad
speeds, the pressures shoul dber eset to the
higher values: R
if you want to drive with an increased load
and/or R
if you want to drive at higher speeds
i The tire pressures for increased load sa nd/
or higher road speeds, shown in the tire pres-
sure table, may have an egative effect on driv-
ing comfort.
If the tire pressure is not set correctly, this can
lea dtoane xcessive build up of heat and as ud-
den loss of pressure.
For more information, contact aq ualifie ds pe-
cialist workshop.
Important notes on tire pressure
G WARNING
If the tire pressure drops repeatedly ,t he
wheel ,v alve or tire may be damaged. Tire
pressure that is too low may resul tina tire
blow-out. There is ar isk 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 unabl etor ectify the damage, con-
tact aq ualifie ds pecialist workshop.
G WARNING
If you fit unsuitable accessorie so nto tire
valves ,t he 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 resul tint ire pressure loss. There is a
risk of an accident.
Only screw the standard valve cap or other
valve caps approved by Mercedes-Benz for
you rv ehicle onto the tire valve.
Use as uitable pressure gauge to check the tire
pressure. The outer appearance of at ire does
not permit any reliable conclusion abou tt he tire
pressure. On vehicle se quipped with the elec-
tronic tire pressure monitor, the tire pressure
can be checked in the on-board computer. The tire temperature and pressure increase
when the vehicle is in motion. This is dependent
on the driving speed and the load.
Therefore, you shoul do nly correct tire pres-
sures when the tires are cold.
The tires are cold: R
if the vehicle has been parked with the tires
out of direct sunlight for at least three hours
and R
if the vehicle has been driven less than 1m ile
(1.6 km)
The tire temperature changes depending on the
outsid et emperature ,t he vehicle speed and the
tire load .Ift he tire temperature changes by
18 ‡( 10 †), the tire pressure changes by
approximately 10 kPa (0.1 bar/1.5 psi) .T ake
this into account when checking 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 resulting valu ew il lbeh ighe rt han if
the tires were cold. This is normal. Do not
reduce the tire pressure to the valu es pecified
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-pilla ront he driver's sideR
in the tire pressure table in the fuel fille rf lap
( Y
page 139)
Underinflated or overinflated tires
Underinflated tires
G WARNING
Tires with pressure that is too low can over-
heat and burst as ac onsequence. In addition,
they also suffer from excessive and/or irreg-
ula rw ear, which can severel yi mpair the brak-
ing propertie sa nd the driving characteristics.
There is ar isk of an accident.
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
adversely affect handling292
Tire pressure
Wheel sa nd tires

R
wear excessively and/or unevenly R
have an adverse effect on fuel consumption
Overinflated tires
G WARNING
Tires with excessively high pressure can burst
becaus et he ya re damaged mor ee asily by
road debris ,p otholes etc .Ina ddition, they
also suffer fro mi rregular wear, which can
severely impair th eb raking properties and the
driving characteristics. Ther eisar isk of an
accident.
Avoid tir ep ressures that are too high in all the
tires, including th es pare wheel.
Overinflated tires may: R
increase th eb raking distanceR
adversely affect handling R
wear excessively and/or unevenly R
have an adverse effect on ride comfort R
be mor es usceptible to damage
Maximu mt ir ep re ssures
C
Example: maximum permissible tir ep res-
sure
Never exceed th em aximum permissible tire
inflatio np ressure. Always observe th er ecom-
mended tir ep ressure for your vehicle when
adjustin gt he tir ep ressure ( Y
page 290).
i The actual values for tires are vehicle-spe-
cific and may deviat ef ro mt he values in the
illustration. Checking th et ir ep re ssures
Important safety notes Observe th en otes on tir ep ressure
( Y
page 290).
Information on air pressure for th et ires on your
vehicle can be found: R
on th ev ehicle's Tire and Loadin gI nf ormation
placar dont he B-pillar R
in th et ir ep ressure table in th ef uel filler flap
( Y
page 139) R
in th e" Tire pressure" section
Checking tir ep re ssures manuallyTo determine and set th ec orrec tt ir ep ressure,
proceed as follows: X
Remov et he valve cap of th et ir et ha tistob e
checked. X
Pres st he tir ep ressure gauge securely onto
th ev alve. X
Read th et ir ep ressure and compare it to the
recommended value on th eT ire and Loading
Information placar dort he tir ep ressure table
( Y
page 290). X
If th et ir ep ressure is too low, increase th et ire
pressure to th er ecommended value. X
If th et ir ep ressure is too high, releas ea ir. To
do so, pres sd own th em etal pin in th ev alve,
using th et ip of ap en for example. Then check
th et ir ep ressure again using th et ir ep ressure
checker. X
Screw th ev alve cap ont ot he valve.X
Repeat these steps for th eo ther tires.
Tir ep re ssur el oss warning system
(Canada only)
General notes While th ev ehicle is in motion, th et ir ep ressure
loss warning system monitors th es et tir ep res-
sure using th er otational speed of th ew heels.
This enables th es ystem to detect significant
pressure loss in at ire. If th es peed of rotation of
aw heel changes as ar esult of al oss of pressure,
ac orresponding warning message will appear in
th em ultifunction display.
You can recognize th et ir ep ressure loss warning
by the Run Flat Indicato rA ctive PressTir ep re ssure 293
Wheels and tires Z

'OK' to Restart message in the multifunction
displa yint he Serv. menu. Information on the
message displa yc an be found in the "Restarting
the tire pressure loss warning" section
( Y
page 294).
Important safety notes The tire pressure warning system does not warn
you of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
( Y
page 290).
The tire pressure loss warning does not replace
the need to regularly check the tire pressure. An
even loss of pressure on several tires at the
same time cannot be detected by the tire pres-
sure loss warning system.
The tire pressure monitor is not able to warn you
of as udden loss of pressure, e.g. if the tire is
penetrated by af oreign object. In the event of a
sudden loss of pressure, bring the vehicle to a
halt by braking carefully .A void abrupt steering
movements.
The function of the tire pressure loss warning
system is limited or delayed if: R
snow chains are mounted on your vehicle's
tires. R
road conditions are wintry. R
you are driving on sand or gravel. R
you adopt av ery sporty driving style (corner-
ing at high speeds or driving with high rates of
acceleration). R
you are driving with ah eavy load (in the vehi-
cle or on the roof)
Restarting the tire pressure loss warn-
ing system Restart the tire pressure loss warning system if
you have: R
changed the tire pressure R
changed the wheels or tires R
mounted new wheels or tires X
Before restarting, make sure that the tire
pressures are set properly on all four tires for
the respective operating conditions.
The recommended tire pressure can be found
on the Tire and Loading Information placard
on the B-pillar. Additionally ,at ire pressure
table is attached to the fuel filler flap. The tire
pressure loss warning system can only give
reliable warnings if you have set the correct tire pressure. If an incorrect tire pressure is
set, these incorrect value sw ill be monitored.X
Also observe the notes in the section on tire
pressures ( Y
page 290). X
Make sure that the SmartKey is in position H
in the ignition lock ( Y
page 122).X
Press Y or e on the steering wheel to
select the Serv. menu.X
Press the c or d button to select
Tire Pressure . X
Press the v button.
The Run Flat Indicator Active Press
'OK' to Restart message appears in the
multifunction display.
If you wish to confirm the restart: X
Press the v button.
The Tire Pressure Now OK? message
appears in the multifunction display. X
Press the c or d button to select Yes .X
Press the v button.
The Run Flat Indicator Restarted mes-
sage appears in the multifunction display.
After at each-in period, the tire pressure loss
warning system will monitor the set tire pres-
sures of all four tires.
If you wish to cance lt he restart:X
Press the 8 button.
or X
If the Tire Pressure Now OK? message
appears, press the c or d button to
select Cancel . X
Press the v button.
The tire pressure value ss tored at the last
restart will continue to be monitored.
Tire pressure monitor (Canada only)
General notes If at ire pressure monitor is installed, the vehi-
cle's wheels have sensors that monitor the tire
pressures in all four tires. The tire pressure mon-
itor warns you if the pressure drops in one or
more of the tires. The tire pressure monitor only
functions if the corresponding sensors are
installed in all wheels.
Information on tire pressures is displayed in the
multifunction display. After af ew minutes of
driving, the current tire pressure of each tire is294
Tire pressure
Wheels and tires

shown in the Serv. menu of the multifunction
display, see illustration (example).
For information on the message display, refer to
the "Checking the tire pressure electronically"
section ( Y
page 296).
Important safety notes
G WARNING
Each tire, including the spare (if provided),
should be checked at least once every two
weeks when cold and inflated to the pressure
recommended by the vehicle manufacturer
on the Tire and Loading Information placard
on the driver's door B-pillar or the tire pres-
sure label on the inside of the fuel filler flap. If
your vehicle has tires of ad ifferent size than
the size indicated on the Tire and Loading
Information placard or, if available, the tire
pressure label ,y ou should determine the
proper tire pressure for those tires.
As an added safety feature, your vehicle has
been equipped with at ire pressure monitoring
system (TPMS) that illuminates al ow tire pres-
sure telltale when one or more of your tires
are significantly underinflated. Accordingly,
when the low tire pressure telltale lights up,
you should stop and check your tires as soon
as possible ,a nd inflate them to the proper
pressure. Driving on as ignificantly underin-
flated tire causes the tire to overheat and can
lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle's
handling and stopping ability. Please note that
the TPMS is not as ubstitute for proper tire
maintenance, and it is the driver's responsi-
bility to maintain correct tire pressure, even if
underinflation has not reached the level to trigger illumination of the TPMS low tire pres-
sure telltale.
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 combined with
the low tire pressure telltale. When the sys-
tem detects am alfunction, the warning lamp
will flash for approximately am inute 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 illu-
minated, the system may not be able to detect
or signal low tire pressure as intended.
TPMS malfunctions may occur for av ariety of
reasons, including the installation of incom-
patible replacement or alternate tires or
wheels on the vehicle that prevent the TPMS
from functionin gp roperly. 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.
It is the driver's responsibility to set the tire
pressure to that recommended for cold tires
which is suitable for the operating situation
( Y
page 290). Note that the correct tire pressure
for the current operating situation must first be
taught-in to the tire pressure monitor. If as ub-
stantial loss of pressure occurs, the warning
threshold for the warning message is aligned to
the taught-in reference values. Restart the tire
pressure monitor after adjusting the pressure of
the cold tires ( Y
page 297). The current pres-
sures are saved as new reference values. As a
result, aw arning message will appea rift he tire
pressure drops significantly.
The tire pressure monitor does not warn you of
an incorrectly set tire pressure. Observe the
notes on the recommended tire pressure
( Y
page 290).
The tire pressure monitor is not able to warn you
of as udden loss of pressure, e.g. if the tire is
penetrated by af oreign object. In the event of a
sudden loss of pressure, bring the vehicle to a
halt by braking carefully .A void abrupt steering
movements. Tire pressure 295
Wheels and tires Z

The tire pressure monitor has ay ellow warning
lamp in the instrument cluster for indicating
pressure loss or am alfunction. Whether the
warning lamp flashes or lights up indicates
whether at ire pressure is too low or the tire
pressure monitor is malfunctioning: R
if the warning lamp is lit continuously, the tire
pressure on one or more tires is significantly
too low. The tire pressure monitor is not mal-
functioning. R
if the warning lamp flashes for around a
minute and then remains lit constantly, the
tire pressure monitor is malfunctioning.
In addition to the warning lamp, am essage
appears in the multifunction display .O bserve
the information on display messages
( Y
page 211).
It may take up to ten minutes for am alfunction
of the tire pressure monitor to be indicated. A
malfunction will be indicated by the tire pres-
sure warning lamp flashing for approximately
one minute and then remaining lit. When the
malfunction has been rectified, the tire pressure
warning lamp goes out after af ew minutes of
driving.
The tire pressure values indicated by the on-
board computer may differ from those meas-
ured at ag as station with ap ressure gauge. The
tire pressures shown by the on-board computer
refer to those measured at sea level. At high
altitudes, the tire pressure values indicated by a
pressure gauge are higher than those shown by
the on-board computer. In this case, do not
reduce the tire pressures.
The operation of the tire pressure monitor can
be affected by interferenc ef rom radio transmit-
ting equipment (e.g. radio headphones, two-way
radios) that may be being operated in or near the
vehicle.
Checking the tire pressur ee lectroni-
cally X
Make sure that the SmartKey is in position H
in the ignition lock ( Y
page 122).X
Press Y or e on the steerin gw heel to
select the Serv. menu.X
Press the c or d button to select
Tire Pressure .X
Press the v button.
The current tire pressure of each tire is shown
in the multifunction display. If the vehicle was parked for longer than
20 minutes, the Tire pressure will be
displayed after driving af ew minutes
message is shown.
After at each-in process, the tire pressure mon-
itor automatically detect sn ew wheels or new
sensors. As long as ac lear allocation of the tire
pressure value to the individual wheels is not
possible, the Tire Pressure Monitor Active
message is shown instead of the tire pressure
display .T he tire pressures are already being
monitored.
If an emergenc ys pare wheel is mounted, the
system may continue to show the tire pressure
of the wheel that has been removed for af ew
minutes. If this occurs, not et hat the value dis-
played for the position where the spare wheel is
mounted is not the same as the current tire
pressure of the emergenc ys pare wheel.
Tire pressur em onitor warning mes-
sages If the tire pressure monitor detect sap ressure
loss in one or more tires, aw arning message is
shown in the multifunction display .T he yellow
tire pressure warning lamp then lights up. R
If the Please Correct Tire Pressure
message appears in the multifunction display,
the tire pressure in at least one tire is too low.
The tire pressure must be corrected when the
opportunit ya rises. R
If the Check Tire Pressure message
appears in the multifunction display ,t he tire
pressure in one or more tires has dropped
significantly. The tires must be checked. R
If the Tire Pressure Warning Tire Fail‐
ure message appears, the tire pressure in one
or more tires has dropped suddenly. The tires
must be checked.
Observe the instructions and safety notes in the
display messages in the "Tires" section
( Y
page 211).
If the wheel positions on the vehicle are rotated,
the tire pressures may be displayed for the
wrong positions for as hort time. This is rectified
after af ew minutes of driving, and the tire pres-
sures are displayed for the correc tp ositions.296
Tir ep re ssure
Wheels and tires

Restarting the tire pressure monitor Whe ny ou restart the tire pressure monitor, all
existing warning messages are deleted and the
warning lamps go out. The monitor uses the cur-
rentl ys et tire pressures as the reference values
for monitoring. In most cases, the tire pressure
monitor will automaticall yd etect the new refer-
ence value sa fte ry ou have changed the tire
pressure. However, yo uc an also set reference
value sm anually as described here. The tire
pressure monitor then monitors the new tire
pressure values. X
Set the tire pressure to the value recommen-
ded for the corresponding driving situation on
the Tire and Loading Information placard on
the driver' ss id eB -pillar ( Y
page 290).
Yo uc an find more tire pressure value sf or
various operating conditions in the tire pres-
sure table inside the fue lf ille rf lap
( Y
page 139). X
Make sure that the tire pressure is correct on
al lf ou rw he els.X
Make sure that the SmartKey is in position H
in the ignition lock ( Y
page 122).X
Press Y or e on the steering wheel to
select the Serv. menu.X
Press the c or d button to select
Tire Pressure .X
Press the v button.
The multifunction display shows the current
tire pressure for each tire or the Tire pres‐
sure will be displayed after driving
af ew minutes message.X
Press the d button.
The multifunction display shows the Use
Current Pressure sasN ew Reference
Values message.
If you wish to confirm the restart: X
Press the v button.
The Tire Press. Monitor Restarted mes-
sage appears in the multifunction display.
After driving for af ew minutes, the system
checks whethe rt he 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 cance lt he restart:X
Press the 8 button.
The tire pressure value ss tore datt he last
restart will continu etobem onitored. Radio type approval for the tire pres-
sure monitor Country Radio type approval number
USA FCC ID: MRXMW2433A
FCCIC ID:MRXGG4 Thi sd evice
complies with part 15 of the FCC
rules and with license exempt
RSS standard sofI ndustry Can-
ada. Operation is subject to the
following conditions .( 1) This
device may not cause harmful
interference, and (2) Thi sd evice
mus ta ccept any interference
received, including interference
that may cause undesired oper-
ation. Le present apparei le st
conforme d'industri eC an ada
applicables au xa pp ereils radio
exempts de licence. L'exploita-
tion est authorisee au xd eu xc on-
ditions suivantes. (1) .L 'appareil
ne doi tp as produire de brouil-
lage, et (2) L'autisatue rdel 'ap-
parei ld oi ta ccepter tou tb rouil-
lage radioelectriqu es ubi, meme
si le brouillag ee st susceptible
d'e nc ompromettre le fonc-
tionnement. WARNING :C ha nges
or modifications not expressively
approved by the party responsi-
bl ef or compliance could voi dt he
users authority to operate the
equipment. The term "IC:" before
the radio certification number
only signifies Canad at echnical
specifications were met.
FCC ID:MRXMC34MA4 This
device complies with part 15 of
the FCC rules and with license
exempt RSS standard sofI ndus-
try Canada. Operation is subject
to the following conditions .( 1)
Thi sd evice may not cause harm-
ful interference, and (2) This
device mus ta ccept any interfer-
ence receive d, i ncluding interfer-
e nce that may cause undesired
operation. Le present appareil
est conforme d'industri eC an ada
applicables au xa pp ereils radio
exempts de license .L 'exploita-
tion est authorisee au xd eu xc on-
ditions suivantes. (1) .L 'appareilTire pressure 297
Wheel sa nd tires Z