2019 MERCEDES-BENZ CLA warning

a corresponding warning message will appear inthe multifunction display.
You can recognize the tire pressure loss warningby theRun Flat Indicator Active PressRun Flat Indicator Active Press'OK''OK'totoRestartRestartmessage in the multifunctiondisplay in theServ.Serv.menu. Information on themessage display can be found in the "Restartingthe tire pressure loss warning" section(Ypage 297).
Important safety notes
The tire pressure warning system does not warnyou of an incorrectly set tire pressure. Observethe notes on the recommended tire pressure(Ypage 293).
The tire pressure loss warning does not replacethe need to regularly check the tire pressure. Aneven loss of pressure on several tires at thesame time cannot be detected by the tire pres-sure loss warning system.
The tire pressure monitor is not able to warn youof a sudden loss of pressure, e.g. if the tire ispenetrated by a foreign object. In the event of asudden loss of pressure, bring the vehicle to ahalt by braking carefully. Avoid abrupt steeringmovements.
The function of the tire pressure loss warningsystem is limited or delayed if:
Rsnow chains are mounted on your vehicle'stires.
Rroad conditions are wintry.
Ryou are driving on sand or gravel.
Ryou adopt a very sporty driving style (corner-ing at high speeds or driving with high rates ofacceleration).
Ryou are driving with a heavy load (in the vehi-cle or on the roof)
Restarting the tire pressure loss warn-
ing system
Restart the tire pressure loss warning system ifyou have:
Rchanged the tire pressure
Rchanged the wheels or tires
Rmounted new wheels or tires
XBefore restarting, make sure that the tirepressures are set properly on all four tires forthe respective operating conditions.
The recommended tire pressure can be foundon the Tire and Loading Information placard
on the B-pillar. Additionally, a tire pressuretable is attached to the fuel filler flap. The tirepressure loss warning system can only givereliable warnings if you have set the correcttire pressure. If an incorrect tire pressure isset, these incorrect values will be monitored.
XAlso observe the notes in the section on tirepressures (Ypage 293).
XMake sure that the SmartKey is in positionHin the ignition lock (Ypage 123).
XPressYoreon the steering wheel toselect theServ.Serv.menu.
XPress thecordbutton to selectTire PressureTire Pressure.
XPress thevbutton.TheRun Flat Indicator Active PressRun Flat Indicator Active Press'OK' to Restart'OK' to Restartmessage appears in themultifunction display.
If you wish to confirm the restart:
XPress thevbutton.TheTire Pressure Now OK?Tire Pressure Now OK?messageappears in the multifunction display.
XPress thecordbutton to selectYesYes.
XPress thevbutton.TheRun Flat Indicator RestartedRun Flat Indicator Restartedmes-sage appears in the multifunction display.
After a teach-in period, the tire pressure losswarning system will monitor the set tire pres-sures of all four tires.
If you wish to cancel the restart:
XPress the8button.
or
XIf theTire Pressure Now OK?Tire Pressure Now OK?messageappears, press thecordbutton toselectCancelCancel.
XPress thevbutton.The tire pressure values stored at the lastrestart will continue to be monitored.
Tire pressure monitor (Canada only)
General notes
If a tire pressure monitor is installed, the vehi-cle's wheels have sensors that monitor the tirepressures in all four tires. The tire pressure mon-itor warns you if the pressure drops in one ormore of the tires. The tire pressure monitor onlyfunctions if the corresponding sensors areinstalled in all wheels.
Tire pressure297
Wheels and tires
Z

Information on tire pressures is displayed in themultifunction display. After a few minutes ofdriving, the current tire pressure of each tire isshown in theServ.Serv.menu of the multifunctiondisplay, see illustration (example).
For information on the message display, refer tothe "Checking the tire pressure electronically"section (Ypage 299).
Important safety notes
GWARNING
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 a different size than
the size indicated on the Tire and Loading
Information placard or, if available, the tire
pressure label, you should determine the
proper tire pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring
system (TPMS) that illuminates a low 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, and inflate them to the proper
pressure. Driving on a significantly 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 a substitute 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 a malfunction, the warning lamp
will flash for approximately a minute 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 a variety of
reasons, including the installation of incom-
patible 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.
It is the driver's responsibility to set the tirepressure to that recommended for cold tireswhich is suitable for the operating situation(Ypage 293). Note that the correct tire pressurefor the current operating situation must first betaught-in to the tire pressure monitor. If a sub-stantial loss of pressure occurs, the warningthreshold for the warning message is aligned tothe taught-in reference values. Restart the tirepressure monitor after adjusting the pressure ofthe cold tires (Ypage 300). The current pres-sures are saved as new reference values. As aresult, a warning message will appear if the tirepressure drops significantly.
The tire pressure monitor does not warn you ofan incorrectly set tire pressure. Observe thenotes on the recommended tire pressure(Ypage 293).
The tire pressure monitor is not able to warn youof a sudden loss of pressure, e.g. if the tire ispenetrated by a foreign object. In the event of asudden loss of pressure, bring the vehicle to a
298Tire pressure
Wheels and tires

halt by braking carefully. Avoid abrupt steeringmovements.
The tire pressure monitor has a yellow warninglamp in the instrument cluster for indicatingpressure loss or a malfunction. Whether thewarning lamp flashes or lights up indicateswhether a tire pressure is too low or the tirepressure monitor is malfunctioning:
Rif the warning lamp is lit continuously, the tirepressure on one or more tires is significantlytoo low. The tire pressure monitor is not mal-functioning.
Rif the warning lamp flashes for around aminute and then remains lit constantly, thetire pressure monitor is malfunctioning.
In addition to the warning lamp, a messageappears in the multifunction display. Observethe information on display messages(Ypage 213).
It may take up to ten minutes for a malfunctionof the tire pressure monitor to be indicated. Amalfunction will be indicated by the tire pres-sure warning lamp flashing for approximatelyone minute and then remaining lit. When themalfunction has been rectified, the tire pressurewarning lamp goes out after a few minutes ofdriving.
The tire pressure values indicated by the on-board computer may differ from those meas-ured at a gas station with a pressure gauge. Thetire pressures shown by the on-board computerrefer to those measured at sea level. At highaltitudes, the tire pressure values indicated by apressure gauge are higher than those shown bythe on-board computer. In this case, do notreduce the tire pressures.
The operation of the tire pressure monitor canbe affected by interference from radio transmit-ting equipment (e.g. radio headphones, two-wayradios) that may be being operated in or near thevehicle.
Checking the tire pressure electroni-
cally
XMake sure that the SmartKey is in positionHin the ignition lock (Ypage 123).
XPressYoreon the steering wheel toselect theServ.Serv.menu.
XPress thecordbutton to selectTire PressureTire Pressure.
XPress thevbutton.The current tire pressure of each tire is shownin the multifunction display.
If the vehicle was parked for longer than20 minutes, theTire pressure will beTire pressure will bedisplayed after driving a few minutesdisplayed after driving a few minutesmessage is shown.
After a teach-in process, the tire pressure mon-itor automatically detects new wheels or newsensors. As long as a clear allocation of the tirepressure value to the individual wheels is notpossible, theTireTirePressurePressureMonitorMonitorActiveActivemessage is shown instead of the tire pressuredisplay. The tire pressures are already beingmonitored.
If an emergency spare wheel is mounted, thesystem may continue to show the tire pressureof the wheel that has been removed for a fewminutes. If this occurs, note that the value dis-played for the position where the spare wheel isfitted is not the same as the current tire pres-sure of the emergency spare wheel.
Tire pressure monitor warning mes-
sages
If the tire pressure monitor detects a pressureloss in one or more tires, a warning message isshown in the multifunction display. The yellowtire pressure warning lamp then lights up.
RIf thePlease Correct Tire PressurePlease 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 theopportunity arises.
RIf theCheck Tire PressureCheck Tire Pressuremessageappears in the multifunction display, the tirepressure in one or more tires has droppedsignificantly. The tires must be checked.
RIf theTireTirePressurePressureWarningWarningTireTireFail‐Fail‐ureuremessage appears, the tire pressure in oneor more tires has dropped suddenly. The tiresmust be checked.
Observe the instructions and safety notes in thedisplay messages in the "Tires" section(Ypage 213).
If the wheel positions on the vehicle are rotated,the tire pressures may be displayed for thewrong positions for a short time. This is rectifiedafter a few minutes of driving, and the tire pres-sures are displayed for the correct positions.
Tire pressure299
Wheels and tires
Z

Restarting the tire pressure monitor
When you restart the tire pressure monitor, allexisting warning messages are deleted and thewarning lamps go out. The monitor uses the cur-rently set tire pressures as the reference valuesfor monitoring. In most cases, the tire pressuremonitor will automatically detect the new refer-ence values after you have changed the tirepressure. However, you can also set referencevalues manually as described here. The tirepressure monitor then monitors the new tirepressure values.
XSet the tire pressure to the value recommen-ded for the corresponding driving situation onthe Tire and Loading Information placard onthe driver's side B-pillar (Ypage 293).
You can find more tire pressure values forvarious operating conditions in the tire pres-sure table inside the fuel filler flap(Ypage 141).
XMake sure that the tire pressure is correct onall four wheels.
XMake sure that the SmartKey is in positionHin the ignition lock (Ypage 123).
XPressYoreon the steering wheel toselect theServ.Serv.menu.
XPress thecordbutton to selectTire PressureTire Pressure.
XPress thevbutton.The multifunction display shows the currenttire pressure for each tire or theTire pres‐Tire pres‐suresurewillwillbebedisplayeddisplayedafterafterdrivingdrivinga few minutesa few minutesmessage.
XPress thedbutton.The multifunction display shows theUseUseCurrent Pressures as New ReferenceCurrent Pressures as New ReferenceValuesValuesmessage.
If you wish to confirm the restart:
XPress thevbutton.TheTireTirePress.Press.MonitorMonitorRestartedRestartedmes-sage appears in the multifunction display.
After driving for a few minutes, the systemchecks whether the current tire pressures arewithin the specified range. The new tire pres-sures are then accepted as reference valuesand monitored.
If you wish to cancel the restart:
XPress the8button.The tire pressure values stored at the lastrestart will continue to be monitored.
Radio type approval for the tire pres-
sure monitor
CountryRadio type approval number
USAFCC ID: MRXMW2433A
FCCIC ID:MRXGG4 This devicecomplies with part 15 of the FCCrules and with license exemptRSS standards of Industry Can-ada. Operation is subject to thefollowing conditions. (1) Thisdevice may not cause harmfulinterference, and (2) This devicemust accept any interferencereceived, including interferencethat may cause undesired oper-ation. Le present appareil estconforme d'industrie Canadaapplicables aux appareils radioexempts de licence. L'exploita-tion est authorisee aux deux con-ditions suivantes. (1). L'appareilne doit pas produire de brouil-lage, et (2) L'autisateur de l'ap-pareil doit accepter tout brouil-lage radioelectrique subi, memesi le brouillage est susceptibled'en compromettre le fonc-tionnement. WARNING: Changesor modifications not expressivelyapproved by the party responsi-ble for compliance could void theusers authority to operate theequipment. The term "IC:" beforethe radio certification numberonly signifies Canada technicalspecifications were met.
FCC ID:MRXMC34MA4 Thisdevice complies with part 15 ofthe FCC rules and with licenseexempt RSS standards of Indus-try Canada. Operation is subjectto the following conditions. (1)This device may not cause harm-ful interference, and (2) Thisdevice must accept any interfer-ence received, including interfer-ence that may cause undesiredoperation. Le present appareilest conforme d'industrie Canadaapplicables aux appareils radioexempts de license. L'exploita-tion est authorisee aux deux con-ditions suivantes. (1). L'appareil
300Tire pressure
Wheels and tires

CountryRadio type approval number
ne doit pas produire de brouil-lage, et (2) L'autisatuer de l'ap-pareil doit accepter tout brouil-lage radioelectrique subi, memesi le brouillage est susceptibled'en compromettre le fonc-tionnement. WARNING: Changesor modifications not expressivelyapproved by the party responsi-ble for compliance could void theusers authority to operate theequipment. The term "IC:" beforethe radio certification numberonly signifies Canada technicalspecifications were met.
CanadaIC: 2546A-MW2433A
IC:2546A-GG4 This device com-plies with part 15 of the FCCrules and with license exemptRSS standards of Industry Can-ada. Operation is subject to thefollowing conditions. (1) Thisdevice may not cause harmfulinterference, and (2) This devicemust accept any interferencereceived, including interferencethat may cause undesired oper-ation. Le present appareil estconforme d'industrie Canadaapplicables aux appareils radioexempts de license. L'exploita-tion est authorisee aux deux con-ditions suivantes. (1). L'appareilne doit pas produire de brouil-lage, et (2) L'autisateur de l'ap-pareil doit accepter tout brouil-lage radioelectrique subi, memesi le brouillage est susceptibled'en compromettre le fonc-tionnement. WARNING: Changesor modifications not expressivelyapproved by the party responsi-ble for compliance could void theusers authority to operate theequipment. The term "IC:" beforethe radio certification numberonly signifies Canada technicalspecifications were met.
IC: 2546A-MC34MA4
Loading the vehicle
Instruction labels for tires and loads
GWARNING
Overloaded tires can overheat, causing a
blowout. Overloaded tires can also impair the
steering and driving characteristics and lead
to brake failure. There is a risk of accident.
Observe the load rating of the tires. The load
rating must be at least half of the GAWR of
your vehicle. Never overload the tires by
exceeding the maximum load.
Two instruction labels on your vehicle show themaximum possible load.
(1) The Tire and Loading Information placard ison the B-pillar on the driver's side. The Tireand Loading Information placard shows themaximum permissible number of occu-pants and the maximum permissible vehicleload. It also contains details of the tire sizesand corresponding pressures for tiresmounted at the factory.
(2) The vehicle identification plate is on the B-pillar on the driver's side. The vehicle iden-tification plate informs you of the grossvehicle weight rating. It is made up of thevehicle weight, all vehicle occupants, thefuel and the cargo. You can also find infor-mation about the maximum gross axleweight rating on the front and rear axle.
The maximum gross axle weight rating isthe maximum weight that can be carried byone axle (front or rear axle). Never exceedthe maximum load or the maximum grossaxle weight rating for the front or rear axle.
CB-pillar, driver's side
Loading the vehicle301
Wheels and tires
Z

Observe the legally required minimum tire treaddepth (Ypage 291). Winter tires can reduce thebraking distance on snow-covered surfaces incomparison with summer tires. The braking dis-tance is still much further than on surfaces thatare not icy or covered with snow. Take appro-priate care when driving.
Further information on winter tires (M+S tires)(Ypage 292).
Temperature
GWARNING
The temperature grade for this tire is estab-
lished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla-
tion, or excessive loading, either separately or
in combination, can cause excessive heat
build-up and possible tire failure.
The temperature grades are A (the highest), B,and C, representing the tire's resistance to thegeneration of heat and its ability to dissipateheat when tested under controlled conditionson a specified indoor laboratory test wheel. Sus-tained high temperature can cause the materialof the tire to degenerate and reduce tire life, andexcessive temperature can lead to sudden tirefailure. The grade C corresponds to a level ofperformance which all passenger car tires mustmeet under the Federal Motor Vehicle SafetyStandard No. 109. Grades B and A representhigher levels of performance on the laboratorytest wheel than the minimum required by law.
Tire labeling
Overview
CUniform Tire Quality Grading Standards(Ypage 309)
DDepartment of Transportation, Tire Identifi-cation Number (Ypage 308)

Tire-mounting tools should not be used nearthe valve. This could damage the electroniccomponents.
Only have tires changed at a qualified spe-cialist workshop.
Observe the instructions and safety notes in the"Changing a wheel" section (Ypage 310).
The wear patterns on the front and rear tiresdiffer, depending on the operating conditions.Rotate the wheels before a clear wear patternhas formed on the tires. Front tires typicallywear more on the shoulders and the rear tires inthe center.
On vehicles that have the same size front andrear wheels, you can rotate the wheels accord-ing to the intervals in the tire manufacturer'swarranty book in your vehicle documents. If nowarranty book is available, the tires should berotated every 3,000 to 6,000 miles (5,000 to10,000 km). Depending on tire wear, this maybe required earlier. Do not change the directionof wheel rotation.
Clean the contact surfaces of the wheel and thebrake disc thoroughly every time a wheel is rota-ted. Check the tire pressure and, if necessary,restart the tire pressure loss warning system(Canada only) or the tire pressure monitor (USAonly).
Direction of rotation
Tires with a specified direction of rotation haveadditional benefits, e.g. if there is a risk of hydro-planing. These advantages can only be gained ifthe tires are installed corresponding to thedirection of rotation.
An arrow on the sidewall of the tire indicates itscorrect direction of rotation.
Storing wheels
Store wheels that are not being used in a cool,dry and preferably dark place. Protect the tiresfrom oil, grease, gasoline and diesel.
Mounting a wheel
Preparing the vehicle
XStop the vehicle on solid, non-slippery andlevel ground.
XApply the electric parking brake manually.
XBring the front wheels into the straight-aheadposition.
XShift the transmission to position].
XSwitch off the engine.
XVehicles without KEYLESS-GO:remove theSmartKey from the ignition lock.
XVehicles with KEYLESS-GO start-functionor KEYLESS-GO:open the driver's door.The vehicle electronics are now in position

bolts to come loose. As a result, you could
lose a wheel while driving. There is a risk of
accident.
Never oil or grease wheel bolts. In the event of
damage to the threads, contact a qualified
specialist workshop immediately. Have the
damaged wheel bolts or hub threads
replaced/renewed. Do not continue 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.
Always pay attention to the instructions andsafety notes in the "Changing a wheel" section(Ypage 310).
Only use wheel bolts that have been designedfor the wheel and the vehicle. For safety rea-sons, Mercedes-Benz recommends that youonly use wheel bolts which have been approvedfor Mercedes-Benz vehicles and the respectivewheel.
!To prevent damage to the paintwork, holdthe wheel securely against the wheel hubwhile screwing in the first wheel bolt.
XClean the wheel and wheel hub contact sur-faces.
XPlace the new wheel on the wheel hub andpush 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.
XPlace the ratchet wrench onto the hexagonnut of the jack so that the lettersABare visi-ble.
XTurn the ratchet wrench until the vehicle isonce again standing firmly on the ground.
XPlace the jack to one side.
XTighten the wheel bolts evenly in a crosswisepattern in the sequence indicated (Cto