2019 MERCEDES-BENZ S CLASS tire pressure

Notes on noise or unusual handlingcharac‐teristics
While driving, pay attentiontovibrations, noisesand unusual handlingcharacteristics, e.g. pullingtoone side. This may indicatethatthe wheels ortires are damaged. Ifyou suspectthat a tire isdefective,reduceyour speed immediately.Stopthevehicle as soon as possibletocheckthewheels and tiresfor damage. Hidden tire dam‐age could also be causingthe unusual handlingcharacteristics. Ifyoufind no signs of damage,havethe tires and wheelschecked at aqualifiedspecialistworkshop.
Notes onregularlyinspecting wheels andtires
&WARNINGRisk of accident from dam‐aged tires
Damaged tires can cause tire pressure loss.
As aresult,you could lose control ofyourvehicle.
#Checkthe tiresregularlyfor signs ofdamageandreplace any damaged tiresimmediately.
&WARNINGRisk of aquaplaning duetoinsufficient tire tread
Insufficient tire tread willresult inreducedtire grip. The tire tread is no longer abletodissipatewater.
This meansthat in heavyrain or slushtherisk ofhydroplaning is increased, in particu‐lar ifvehicle speed is not adaptedtosuittheconditions.
Ifthe tire pressure istoo high ortoo low,tires mayexhibit different levels ofwear atdifferent locations onthe tire contact sur‐face.
#Thus,you shouldregularlycheckthetread depth andthe condition ofthe tirecontact surface acrossthe entire widthof all tires.
Minimum tread depthfor:
RSummer tires:

RThe tires maywearexcessively and/orunevenly,which maygreatlyimpair tiretraction.
RThe drivingcharacteristics, aswell assteering and braking, may be greatlyimpaired.
#Comply withtherecommended tirepressure andcheckthe tire pressure ofall tires includingthe spare wheelregu‐larly:
Rat least once a month
Rwhenthe loadchanges
Rbefore embarking on a longer journey
Rif operating conditionschange, e.g. off-road driving
#Adjustthe tire pressure as necessary.
Driving withtire pressurethat istoo high ortoolow can:
RShortenthe service life ofthe tires.
RCause increased tire damage.
RAdversely affect drivingcharacteristics andthus driving safety,e.g. dueto hydroplaning.
&WARNINGRisk of an accident duetoinsufficient tire pressure
Tires with pressurethat istoo low canover‐heat and burstas aresult.
In addition,theyalso suffer fromexcessiveand/or irregularwear, which can significantlyimpairthe braking properties andthe han‐dlingcharacteristics.
#Avoidexcessively low tire pressures inallthe tires, includingthe spare wheel.
Tirepressure which istoo low can cause:
RTiredefects as aresult ofoverheating
RImpaired handlingcharacteristics
RIrregularwear
RIncreased fuel consumption
&WARNINGRisk of accident fromexces‐sive tire pressure
Tires withexcessively high pressure canburst becausetheyare damaged more easilybyhighwayfill, pot holesetc.
In addition,theyalso suffer from irregularwear, which can significantly impairthe brak‐ing properties andthe handlingcharacteris‐tics.
#Avoidexcessively high tire pressures inallthe tires, includingthe spare wheel.
Excessively high tire pressure canresult in:
RIncreased braking distance
RImpaired handlingcharacteristics
RIrregularwear
RImpaired driving comfort
RSusceptibilitytodamage
436Wheels and tires

&WARNINGRisk of accident causedbyrepeated drop in tire pressure
Ifthe tire pressure dropsrepeatedly,thewheel,valve or tire may be damaged.
Insufficient tire pressure can causethe tirestoburst.
#Inspectthe tirefor signs offoreignobjects.
#Check whetherthe wheel orvalve has aleak.
#Ifyou are unabletorectifythe damage,contact aqualified specialistworkshop.
You canfind information on tire pressureforthevehicle'sfactory-installed tires onthefollowinglabels:
RTireand Loading Information placard ontheB‑pillar ofyourvehicle (→page442).
RTirepressuretable onthe inside ofthe fuelfillerflap (→page 437).
Observethe maximum tire pressure(→page448).
Use a suitable tire pressuregaugetocheckthetire pressure. The outer appearance of a tiredoes not permit anyreliable conclusion aboutthe tire pressure.
Vehicles with a tire pressure monitoring sys‐tem:You can alsocheckthe tire pressure usingthe on-board computer.
Only correct tire pressure whenthe tires arecold. Conditionsfor cold tires:
RThevehicle has been parked withthe tiresout of direct sunlightfor at leastthree hours.
RThevehicle has traveled lessthan 1 mile(1.6 km).
Arise inthe tiretemperature of18°F (10 °C)increasesthe tire pressurebyapprox.10kPa(0.1 bar/1.5 psi).Takethis into account whencheckingthe tire pressure ofwarmtires.
The tire pressure recommendedfor increasedload/speed inthe tire pressuretable can affecttheride comfort.
&WARNINGRisk of accident from unsuita‐ble accessories onthe tirevalves
Ifyou mount unsuitable accessories ontotirevalves,the tirevalves may beoverloaded andmalfunction, which can cause tire pressureloss.Tirepressure monitoring systemsforretrofitting will causethe tirevalvetoremainopen. This can alsoresult in tire pressureloss.
#Only screwstandardvalve caps orvalvecaps specifically approvedbyMercedes-Benzforyourvehicle ontothe tirevalve.
Tirepressure table
The tire pressuretable is onthe inside ofthefuelfillerflap.
%The data shown inthe images isexampledata.
Wheels and tires437

The tire pressuretable shows therecommendedtire pressurefor all tires approvedforthisvehi‐cle. Therecommended tire pressures applyforcold tires undervarious operating conditions, i.e.loading and/or speed ofthevehicle.
If one or more tire sizes precede a tire pressure,the tire pressure informationfollowing is onlyvalidforthose tire sizes.
The load conditions "partially laden" and "fullyladen" are defined inthetablefor different num‐bersof passengers and amounts of luggage. Theactual number of seats may differ fromthis.
Some tire pressuretables only showtherimdiameter instead ofthe completetire size, e.g.R18. Therim diameter is part ofthe tire size andcan befound onthe tire sidewall (→page449).
Be suretoalso observethefollowing furtherrelated subjects:
RNotes on tire pressure (→page 435)
RTireand Loading Information placard(→page442)
RMaximum tire pressure (→page448)
Checkingtire pressures manually
#Readthe tire pressureforthe current operat‐ing conditions fromtheTireand LoadingInformation placard orthe tire pressuretable. Observethe notes on tire pressure.
#Removethevalve cap ofthe tiretobechecked.
#Pressthe tire pressuregauge securely ontothevalve.
#Readthe tire pressure.
#Ifthe tire pressure is lowerthantherecom‐mendedvalue, increasethe tire pressuretotherecommendedvalue.
#Ifthe tire pressure is higherthantherecom‐mendedvalue,release air.Todo so, pressdownthe metal pin inthevalve, e.g. usingthe tip of a penforexample. Thencheckthetire pressureagain usingthe tire pressuregauge.
#Screwthevalve cap ontothevalve.
438Wheels and tires

Furtherrelated subjects:
RNotes on tire pressure (→page 435)
RTirepressuretable (→page 437)
RTireand Loading Information placard(→page442)
Tirepressure monitoring system
Function ofthe tire pressure monitoring sys‐tem
&DANGERRisk of accident duetoincor‐rect tire pressure
Every tire, includingthe spare (if provided),should bechecked when cold at least once amonth and inflatedtothe pressurerecom‐mendedbythevehicle manufacturer (seeTireand Loading Information placard ontheB-pillar onthe driver’sside orthe tire pres‐sure label onthe inside ofthe fuelfillerflapofyourvehicle). Ifyourvehicle has tires of adifferent sizethanthe size indicated ontheTireand Loading Information placard orthe
tire pressuretable,you needtodeterminethe proper tire pressureforthose tires.
As an added safetyfeature,yourvehicle hasbeen equipped with a tire pressure monitor‐ing system (TPMS)that illuminates a low tirepressure indicator lamp when one or more ofyour tires are significantly underinflated.Accordingly, ifthe low tire pressure indicatorlamp lights up,you shouldstop andcheckyour tires as soon as possible, and inflatethemtothe proper pressure. Driving on asignificantly underinflated tire causesthe tiretooverheat and can leadtotirefailure.Underinflation also increases fuel consump‐tion andreduces tire tread life, and mayaffectthevehicle's handling and braking abil‐ity. Please notethatthe TPMS is not a substi‐tutefor proper tire maintenance, and it isthedriver'sresponsibilitytomaintain correct tirepressure,even if underinflation has notreachedthe leveltotrigger illumination ofthe TPMS low tire pressure indicator lamp.
Yourvehicle has also been equipped with aTPMS malfunction indicatortoindicate when
the system is not operating properly. TheTPMS malfunction indicator is combined withthe low tire pressure indicator lamp. Whenthe system detects a malfunction,the indica‐tor lamp willflashfor approximatelya minuteandthenremain continuously illuminated.This sequence will continue upon subsequentvehiclestart-ups as long asthe malfunctionexists.
Whenthe malfunction indicator is illumina‐ted,the system may not be abletodetect orsignal low tire pressure as intended. TPMSmalfunctions may occurfor avariety ofrea‐sons, includingthe installation of incompati‐blereplacement or alternate tires or wheelsonthevehiclethat preventthe TPMS fromfunctioning properly.
Alwayscheckthe TPMS malfunctionwarninglamp afterreplacing one or more tires orwheels onyourvehicletoensurethatthereplacement or alternate tires and wheelsallowthe TPMStocontinuetofunction prop‐erly.
Wheels and tires439

The systemchecksthe tire pressure andthe tiretemperature ofthe tires installed onthevehiclebymeans of a tire pressuresensor.
New tire pressure sensors, e.g. in winter tires,are automaticallytaught-in duringthefirst jour‐neytheyare used.
The tire pressure appears inthe multifunctiondisplay (→page 255).
Ifthere is a substantial pressure loss or ifthetiretemperature isexcessive,you will bewarnedinthefollowingways:
Rvia display messages (→page511)
Rviathewwarning lamp inthe instrumentcluster (→page 533)
The tire pressuremonitoring system is only anaid. It isthe driver'sresponsibilitytosetthe tirepressuretotherecommended cold tire pressuresuitableforthe operating situation. Setthe tirepressurefor cold tires using a tire pressuregauge. Notethatthe correct tire pressureforthecurrent operating situation mustfirst betaught-intothe tire pressure monitoring system.
In most cases,the tire pressure monitoring sys‐tem will automatically updatethe newreferencevalues afteryou havechangedthe tire pressure.You can, however,also updatethereferenceval‐uesbyrestartingthe tire pressure monitoringsystem manually (→page441).
System limitations
The system may be impaired or may not functioninthefollowing situations:
RIfthe tire pressure is set incorrectly
RIfthere is a sudden pressure loss caused,forexample,byaforeign object penetratingthetire
RIfthere is a malfunction causedbyanotherradio signal source
Make suretoobservethefollowing furtherrela‐ted subject:
RNotes on tire pressure (→page 435)
Checkingthe tire pressure withthe tire pres‐sure monitoring system
Requirements:RThe ignition is switched on.
On-board computer:
,Service.Tires
One ofthefollowing displaysappears:
RCurrent tire pressure of eachwheel:
RTire pressure will be displayed after driving afew minutes
RTire Pressure Monitor Active:theteach-inprocess ofthe system is notyet complete.The tire pressure are already being moni‐tored.
#Comparethe tire pressure withtherecom‐mended tire pressureforthe current operat‐
440Wheels and tires

ing condition (→page 437). Observethenotes on tiretemperature (→page 435).
%Thevalues displayed inthe multifunction dis‐play may deviate fromthose ofthe tire pres‐suregauge astheyrefertosea level.Athighaltitudes,the tire pressurevalue indicatedbya pressuregauge are higherthanthoseshownbythe on-board computer. Inthiscase, do notreducethe tire pressure.
Make suretoobservethefollowing furtherrela‐ted subject:
RNotes on tire pressure (→page 435)
Restartingthe tire pressure monitoring sys‐tem
Requirements:RTherecommended tire pressure is correctlysetfortherespective operating condition oneach ofthefour wheels (→page 435).
Restartthe tire pressure monitoring system inthefollowing situations:
RThe tire pressure haschanged.
RThe wheels or tires havebeenchanged ornewly installed.
On-board computer:
,Service.Tires
#Swipe downwards onTouch Control ontheleft-hand side ofthesteering wheel.TheUse Current Pressures as New Refer-ence Values?message is shown inthe multi‐function display.
#Pressvtoconfirmtherestart.TheRun Flat Indicator Restartedmessage isshown inthe multifunction display.
Currentwarning messages are deleted andthewyellowwarning lamp goes out.
Afteryou havedrivenfor afew minutes,thesystemcheckswhetherthe current tire pres‐sures are withinthe specifiedrange. The cur‐rent tire pressures arethen accepted asref‐erencevalues and monitored.
Make suretoobservethefollowing furtherrela‐ted subject:
RNotes on tire pressure (→page 435)
Radio equipment approval ofthe tire pres‐sure monitoring system
Radio equipment approval numbers
CountryRadio type approval number
Canada IC: 2546A-GG4T
IC: 2546A-DG6W2D4
IC: 2546A-MC34MA4
Le présent appareil est conformeaux CNR d'Industrie Canadaapplicables aux appareilsradioexempts de licence. L'exploita‐tion est autorisée aux deux con‐ditions suivantes:
(1) l'appareil ne doit pas produirede brouillage,et
(2) l'utilisateur de l'appareil doitacceptertout brouillageradioé‐lectrique subi, même si le
brouillage est susceptible d'encompromettrelefonctionnement.
Wheels and tires441

%The data shown inthe illustration isexampledata.
TheTireand Loading Information placard shows:
RMaximum number of seats2accordingtothe maximum number of people permittedtotravel inthevehicle.
RMaximum permissible load3comprisesthegrossweight of allvehicle occupants, loadand luggage.
RRecommended tire pressures1for coldtires. Therecommended tire pressures arevalidforthe maximum permissible load anduptothe maximum permissiblevehiclespeed.
Please also note:
RInformation on permissibleweights and loadsonthevehicle identification plate(→page 466).
RInformation on tire pressure inthe tire pres‐suretable (→page 437).
Furtherrelated subjects:
RDeterminingthe maximum permissible load(→page443)
RNotes on tire pressure (→page 435).
Determiningthe maximum permissible load
Thefollowingsteps havebeen developed asrequired of all manufacturers underTitle 49,Code ofU.S.FederalRegulations,Part575, pur‐suanttothe "NationalTraffic and MotorVehicleSafetyAct of1966".
#Step 1:locatethestatement "The combinedweight of occupants and load should neverexceed XXXkgor XXX lbs." ("The combinedweight of occupants and load should neverexceed XXXkgor XXX lbs.") onyourvehicle'sTireand Loading Information placard.
#Step 2:determinethe combinedweight ofthe driver and passengersthat will be travel‐ing inyourvehicle.
#Step 3:subtractthe combinedweight ofthedriver and passengers from XXXkgorXXX lbs.
#Step 4:theresultingfigure equalsthe per‐missible cargo and luggage load capacity.Forexample: If "XXX" equals1400 lbs andtherearefiveoccupants inyourvehicle with aweight of150 lbs each,the maximum cargoand luggage load capacity is 650 lbs (1400 -750 (5 x150) = 650 lbs).
#Step 5:determinethe combinedweight ofluggage and loadthatthevehicle will be car‐rying.For safetyreasons,thisweight may notsafelyexceedtheavailable cargo and lug‐gageload capacity calculated instep 4.
Wheels and tires443