2019 MERCEDES-BENZ GLA fuel pressure

Tire pressure not reached
If a pressure of 180 kPa (1.8 bar/26 psi) hasnot been attained after five minutes:
XSwitch off the tire inflation compressor.
XUnscrew the filler hose from the valve of thefaulty tire.
Note that tire sealant may escape when youunscrew the filler hose.
XUSA only:very slowly drive the vehicle for-wards or reverse approximately 30 ft(10m).
XPump upthe tire again.
After a maximum of five minutes the tirepressure must be at least 180 kPa (1.8 bar/26 psi).
GWARNING
If the required tire pressure is not reached
after the specified time, the tire is too badly
damaged. The tire sealant cannot repair the
tire in this instance. Damaged tires and a
tire pressure that is too low can significantly
impair the vehicle's braking and driving
characteristics. There is a risk of accident.
Do not continue driving. Contact a qualified
specialist workshop.
Tire pressure reached
GWARNING
A tire temporarily sealed with tire sealant
impairs the vehicle's driving characteristics
and is not suitable for driving at higher
speeds. There is a risk of an accident.
Adapt your driving style accordingly and
drive carefully. Do not exceed the maximum
permissible speed for a tire sealed with tire
sealant.
USA only:The maximum permissible speedfor a tire sealed with tire sealant is 50 mph(80 km/h). The upper part of the TIREFITsticker must be affixed to the instrument clus-ter in the driver's field of vision.
If a tire pressure of 180 kPa (1.8 bar/26 psi)has been attained after five minutes:
XSwitch off the tire inflation compressor.
XUnscrew the filler hose from the valve of thefaulty tire.Note that tire sealant may escape when youunscrew the filler hose.
XUSA only:Stow the tire sealant bottle andthe tire inflation compressor.
XPull away immediately.
XStop after driving for approximately tenminutes and check the tire pressure withthe tire inflation compressor.The tire pressure must now be at least130 kPa (1.3 bar/19 psi).
GWARNING
If the required tire pressure is not reached
after driving for a short period, the tire is too
badly damaged. The tire sealant cannot
repair the tire in this instance. Damaged
tires and a tire pressure that is too low can
significantly impair the vehicle's braking and
driving characteristics. There is a risk of
accident.
Do not continue driving. Contact a qualified
specialist workshop.
iUSA only:In cases such as the one men-tioned above, contact an authorizedMercedes-Benz Center. Or call1-800-FOR-MERCedes (in the USA) or1-800-387-0100 (in Canada).
XUSA only:Correct the tire pressure if it isstill at least 130 kPa (1.3 bar/19 psi). Seethe Tire and Loading Information placard onthe driver's side B-pillar or the tire pressuretable in the fuel filler flap for values.
XTo increase the tire pressure:switch onthe tire inflation compressor.
Flat tire291
Roadside Assistance
Z

Important safety notes
GWARNING
If you install wheels and tires with incorrect
dimensions, the service brake or wheel sus-
pension components may be damaged.
There is a risk of an accident.
Always replace wheels and tires with ones
that comply with the specifications of the
original part.
When replacing wheels, pay attention to the:
RDesignation
RModel
When replacing tires, pay attention to the:
RDesignation
RManufacturer
RModel
GWARNING
A flat tire will severely affect the driving
characteristics as well as the steering and
braking of the vehicle. There is a risk of an
accident.
Tires without run-flat characteristics:
RDo not drive on with a flat tire.
RChange the flat tire immediately with an
emergency spare wheel or spare wheel.
Alternatively, consult a qualified specialist
workshop.
Tires with run-flat characteristics:
RObserve the information and warning
notes on MOExtended tires (run-flat tires).
Accessories that are not approved for yourvehicle by Mercedes-Benz or are not beingused correctly can impair the operating safety.
Before purchasing and using non-approvedaccessories, visit a qualified specialist work-shop and inquire about:
Rsuitability
Rlegal stipulations
Rfactory recommendations
Further information regarding wheels and tirescan be found under "Wheel/tire combinations"(Ypage 329).
You can ask for information regarding permit-ted wheel/tire combinations at an authorizedMercedes-Benz Center.
Information on tire pressure can be found:
Ron the Tire and Loading Information placardon the B-pillar on the driver's side(Ypage 316)
Rin the tire pressure table in the fuel filler flap(Ypage 144)
Runder "Tire pressure" (Ypage 307)
Operation
Information on driving
Check the tire pressure when the vehicle isheavily laden and adjust prior to a trip.
While driving, pay attention to vibrations,noises and unusual handling characteristics,e.g. pulling to one side. This may indicate thatthe wheels or tires are damaged. If you sus-pect that a tire is defective, reduce your speedimmediately. Stop the vehicle as soon as pos-sible to check the wheels and tires for dam-age. Hidden tire damage could also be causingthe unusual handling characteristics. If youfind no signs of damage, have the tires andwheels checked at a qualified specialist work-shop.
When parking your vehicle, make sure that thetires do not get deformed by the curb or otherobstacles. If they cannot be avoided, driveover obstacles such as curbs slowly and at anobtuse angle. Otherwise, you may damage thewheels or tires.
Regular checking of wheels and tires
GWARNING
Damaged tires can cause tire inflation pres-
sure loss. As a result, you could lose control
of your vehicle. There is a risk of accident.
Check the tires regularly for signs of dam-
age and replace any damaged tires immedi-
ately.
304Operation
Wheels and ti res

tions are vehicle-specific and may deviatefrom the data shown here. The tire pressurespecifications that are valid for your vehiclecan be found on the Tire and Loading Infor-mation placard and tire pressure table onthe vehicle.
General notes
The recommended tire pressures for the tiresmounted at the factory can be found on thelabels described here.
Operation with an emergency spare wheel:information on operation with an emergencyspare wheel can be found in the general notesin the "Emergency spare wheel" section(Ypage 329).
Further information on tire pressures can beobtained at a qualified specialist workshop.
Tire and Loading Information placard
CRecommended tire pressures
The Tire and Loading Information placard is onthe B-pillar on the driver's side (Ypage 316).
The Tire and Loading Information placard con-tains the recommended tire pressures for coldtires. The recommended tire pressures arevalid for the maximum permissible load and upto the maximum permissible vehicle speed.
Tire pressure table
The tire pressure table is on the inside of thefuel filler flap. It shows the tire pressure for alltires permitted at the factory for this vehicle;see illustration (example).
The tire pressure table contains the recom-mended pressures for cold tires for variousoperating conditions, i.e. differing load andspeed conditions.
If a tire size precedes a tire pressure, the fol-lowing tire pressure information is only validfor that tire size; see illustration (example).
The load conditions "partially laden" and "fullyladen" are defined in the table for differentnumbers of occupants and amounts of lug-gage. The actual number of seats may differ.
Some tire pressure tables show only the rimdiameters instead of the full tire size, e.g.R18.Rim diameter is part of the tire size and can befound on the tire sidewall (Ypage 320).
308Tire pressure
Wheels and tires

If the tire pressures have been set to the lowervalues for lighter loads and/or lower roadspeeds, the pressures should be reset to thehigher values:
Rif you want to drive with an increased loadand/or
Rif you want to drive at higher speeds
iThe tire pressures for increased loadsand/or higher road speeds, shown in thetire pressure table, may have a negativeeffect on driving comfort.
If the tire pressure is not set correctly, this canlead to an excessive build-up of heat and asudden loss of pressure.
For more information, contact a qualified spe-cialist workshop.
Important notes on tire pressure
GWARNING
If the tire pressure drops repeatedly, the
wheel, valve or tire may be damaged. Tire
pressure that is too low may result in a tire
blow-out. There is a risk of an accident.
RCheck the tire for foreign objects.
RCheck whether the wheel is losing air or
the valve is leaking.
If you are unable to rectify the damage, con-
tact a qualified specialist workshop.
GWARNING
If you fit unsuitable accessories onto tire
valves, the tire valves may be overloaded
and malfunction, which can cause tire pres-
sure loss. Due to their design, retrofitted tire
pressure monitors keep the tire valve open.
This can also result in tire pressure loss.
There is a risk of an accident.
Only screw the standard valve cap or other
valve caps approved by Mercedes-Benz for
your vehicle onto the tire valve.
Use a suitable pressure gauge to check thetire pressure. The outer appearance of a tiredoes not permit any reliable conclusion aboutthe tire pressure. On vehicles equipped withthe electronic tire pressure monitor, the tire
pressure can be checked in the on-board com-puter.
The tire temperature and pressure increasewhen the vehicle is in motion. This is depend-ent on the driving speed and the load.
Therefore, you should only correct tire pres-sures when the tires are cold.
The tires are cold:
Rif the vehicle has been parked with the tiresout of direct sunlight for at least three hoursand
Rif the vehicle has been driven less than1 mile (1.6 km)
The tire temperature changes depending onthe outside temperature, the vehicle speedand the tire load. If the tire temperaturechanges by 18 ‡ (10 †), the tire pressurechanges by approximately 10 kPa (0.1 bar/1.5 psi). Take this into account when checkingthe pressure of warm tires. Only correct thetire pressure if it is too low for the currentoperating conditions. If you check the tirepressure when the tires are warm, the result-ing value will be higher than if the tires werecold. This is normal. Do not reduce the tirepressure to the value specified for cold tires.The tire pressure would otherwise be too low.
Observe the recommended tire pressures forcold tires:
Ron the Tire and Loading Information placardon the B-pillar on the driver's side
Rin the tire pressure table in the fuel filler flap(Ypage 144)
Underinflated or overinflated tires
Underinflated tires
GWARNING
Tires with pressure that is too low can over-
heat and burst as a consequence. In addi-
tion, they also suffer from excessive and/or
irregular wear, which can severely impair the
braking properties and the driving character-
istics. There is a risk of an accident.
Avoid tire pressures that are too low in all
the tires, including the spare wheel.
Tire pressure309
Wheels and tires
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Underinflated tires may:
Roverheat, leading to tire defects
Radversely affect handling
Rwear excessively and/or unevenly
Rhave an adverse effect on fuel consumption
Overinflated tires
GWARNING
Tires with excessively high pressure can
burst because they are damaged more eas-
ily by road debris, potholes etc. In addition,
they also suffer from irregular wear, which
can severely impair the braking properties
and the driving characteristics. There is a
risk of an accident.
Avoid tire pressures that are too high in all
the tires, including the spare wheel.
Overinflated tires may:
Rincrease the braking distance
Radversely affect handling
Rwear excessively and/or unevenly
Rhave an adverse effect on ride comfort
Rbe more susceptible to damage
Maximum tire pressures
CExample: maximum permissible tire pres-sure
Never exceed the maximum permissible tireinflation pressure. Always observe the recom-mended tire pressure for your vehicle whenadjusting the tire pressure (Ypage 307).
iThe actual values for tires are vehicle-spe-cific and may deviate from the values in theillustration.
Checking the tire pressures
Important safety notes
The tire pressure monitor does not warn youof:
Rincorrectly set tire pressure
Rsudden loss of tire pressure, e.g. from a for-eign object that has penetrated the tire
Observe the notes on tire pressure(Ypage 307).
Information on air pressure for the tires onyour vehicle can be found:
Ron the vehicle's Tire and Loading Informa-tion placard on the B-pillar
Rin the tire pressure table in the fuel filler flap(Ypage 144)
Rin the "Tire pressure" section
Checking tire pressures manually
To determine and set the correct tire pressure,proceed as follows:
XRemove the valve cap of the tire that is tobe checked.
XPress the tire pressure gauge securely ontothe valve.
XRead the tire pressure and compare it to therecommended value on the Tire and LoadingInformation placard or the tire pressuretable (Ypage 307).
XIf the tire pressure is too low, increase thetire pressure to the recommended value.
XIf the tire pressure is too high, release air.To do so, press down the metal pin in thevalve, using the tip of a pen for example.Then check the tire pressure again using thetire pressure checker.
XScrew the valve cap onto the valve.
XRepeat these steps for the other tires.
Tire pressure loss warning system
(Canada only)
General notes
While the vehicle is in motion, the tire pres-sure loss warning system monitors the set tirepressure using the rotational speed of thewheels. This enables the system to detect sig-nificant pressure loss in a tire. If the speed of
310Tire pressure
Wheels and tires

rotation of a wheel changes as a result of aloss of pressure, a corresponding warningmessage will appear in the multifunction dis-play.
You can recognize the tire pressure loss warn-ing by theRun Flat Indicator ActiveRun Flat Indicator ActivePress 'OK' to RestartPress 'OK' to Restartmessage in the mul-tifunction display in theServ.Serv.menu. Informa-tion on the message display can be found inthe "Restarting the tire pressure loss warning"section (Ypage 311).
Important safety notes
The tire pressure warning system does notwarn you of an incorrectly set tire pressure.Observe the notes on the recommended tirepressure (Ypage 307).
The tire pressure loss warning does notreplace the need to regularly check the tirepressure. An even loss of pressure on severaltires at the same time cannot be detected bythe tire pressure loss warning system.
The tire pressure monitor is not able to warnyou of a sudden loss of pressure, e.g. if thetire is penetrated by a foreign object. In theevent of a sudden loss of pressure, bring thevehicle to a halt by braking carefully. Avoidabrupt steering movements.
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 ratesof acceleration).
Ryou are driving with a heavy load (in thevehicle or on the roof)
Restarting the tire pressure loss warn-
ing system
Restart the tire pressure loss warning systemif you 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 tiresfor the respective operating conditions.
The recommended tire pressure can befound on the Tire and Loading Informationplacard on the B-pillar. Additionally, a tirepressure table is attached to the fuel fillerflap. The tire pressure loss warning systemcan only give reliable warnings if you haveset the correct tire pressure. If an incorrecttire pressure is set, these incorrect valueswill be monitored.
XAlso observe the notes in the section on tirepressures (Ypage 307).
XMake sure that the SmartKey is in positionHin the ignition lock (Ypage 125).
XPressYoreon the steering wheelto select 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 pressureloss warning system will monitor the set tirepressures 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
Tire pressure311
Wheels and tires
Z

monitor warns you if the pressure drops in oneor more of the tires. The tire pressure monitoronly functions if the corresponding sensorsare installed in all wheels.
Information on tire pressures is displayed inthe multifunction display. After a few minutesof driving, the current tire pressure of each tireis shown in theServ.Serv.menu of the multifunc-tion display, see illustration (example).
For information on the message display, referto the "Checking the tire pressure electroni-cally" section (Ypage 313).
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 pres-
sure recommended by the vehicle manufac-
turer on the Tire and Loading Information
placard on the driver's door B-pillar or the
tire pressure label on the inside of the fuel
filler flap. If your vehicle has tires of a differ-
ent size than the size indicated on the Tire
and Loading Information placard or, if availa-
ble, 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 monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires are significantly underinflated. Accord-
ingly, 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 signifi-
cantly underinflated 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 vehi-
cle's handling and stopping ability. Please
note that the TPMS is not a substitute for
proper tire maintenance, and it is the driv-
er's responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of
the TPMS low tire pressure 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
system 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 vehicle is started as long as the malfunc-
tion exists. When the malfunction indicator
is illuminated, the system may not be able to
detect or signal low tire pressure as inten-
ded.
TPMS malfunctions may occur for a variety
of reasons, including the installation of
incompatible 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 307). Note that the correct tire pres-sure for the current operating situation mustfirst be taught-in to the tire pressure monitor.If a substantial loss of pressure occurs, thewarning threshold for the warning message isaligned to the taught-in reference values.Restart the tire pressure monitor after adjust-ing the pressure of the cold tires(Ypage 314). The current pressures aresaved as new reference values. As a result, awarning message will appear if the tire pres-sure drops significantly.
312Tire pressure
Wheels and tires

Observe the instructions and safety notes inthe display messages in the "Tires" section(Ypage 223).
If the wheel positions on the vehicle are rota-ted, the tire pressures may be displayed forthe wrong positions for a short time. This isrectified after a few minutes of driving, and thetire pressures are displayed for the correctpositions.
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 thecurrently set tire pressures as the referencevalues for monitoring. In most cases, the tirepressure monitor will automatically detect thenew reference values after you have changedthe tire pressure. However, you can also setreference values manually as described here.The tire pressure monitor then monitors thenew tire pressure values.
XSet the tire pressure to the value recom-mended for the corresponding driving situa-tion on the Tire and Loading Informationplacard on the driver's sideB-pillar (Ypage 307).
You can find more tire pressure values forvarious operating conditions in the tire pres-sure table inside the fuel filler flap(Ypage 144).
XMake sure that the tire pressure is correcton all four wheels.
XMake sure that the SmartKey is in positionHin the ignition lock (Ypage 125).
XPressYoreon the steering wheelto select theServ.Serv.menu.
XPress thecordbutton to selectTire PressureTire Pressure.
XPress thevbutton.The multifunction display shows the currenttire pressure for each tire or theTireTirepressure will be displayed afterpressure will be displayed afterdriving a few minutesdriving a 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.TheTire Press. Monitor RestartedTire Press. Monitor Restartedmessage appears in the multifunction dis-play.
After driving for a few minutes, the systemchecks whether the current tire pressuresare within the specified range. The new tirepressures are then accepted as referencevalues and monitored.
If you wish to cancel the restart:
XPress the8button.The tire pressure values stored at the lastrestart will continue to be monitored.
314Tire pressure
Wheels and tires