warning MERCEDES-BENZ GLA-Class 2017 X156 Owner's Manual

set the correct tire pressure. If an incorrect
tire pressure is set, these incorrect values
will be monitored.
XAlso observe the notes in the section on tire
pressures (
Ypage 343).
XMake sure that the SmartKey is in position
2in the ignition lock (
Ypage 149).
XPress =or; on the steering wheel
to select the Serv.
menu.
XPress the9or: button to select
Tire Pressure
.
XPress the abutton.
The Run Flat Indicator Active
Press 'OK' to Restartmessage
appears in the multifunction display.
If you wish to confirm the restart:
XPress the abutton.
The Tire Pressure Now OK?
message
appears in the multifunction display.
XPress the 9or: button to select
Yes
.
XPress the abutton.
The Run Flat Indicator Restarted
message appears in the multifunction dis-
play.
After a teach-in period, the tire pressure
loss warning system will monitor the set
tire pressures of all four tires.
If you wish to cancel the restart:
XPress the %button.
or
XIf the Tire Pressure Now OK?message
appears, press the 9or: button to
select Cancel
.
XPress the abutton.
The tire pressure values stored at the last
restart will continue to be monitored.
Tire pressure monitor
General notes
If a tire pressure monitor is installed, the vehi-
cle's wheels have sensors that monitor the
tire pressures in all four tires. The tire pres-
sure monitor 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 a few minutes
of driving, the current tire pressure of each
tire is shown in the Serv.
menu of the multi-
function display, see illustration (example).
For information on the message display, refer
to the "Checking the tire pressure electroni-
cally" section (
Ypage 350).
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,
348Tire pressure
Wheels and tires

when the low tire pressure telltale lights up,
you should stop and check your tires as soonas 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 withthe 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 tellt
ale 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
(
Ypage 343). Note that the correct tire pres-
sure for the current operating situation must
first be taught-in to the tire pressure monitor.
If there is a substantial loss of pressure, the
warning threshold for the warning message is aligned to the reference values taught-in.
Restart the tire pressure monitor after adjust-
ing the pressure of the cold tires
(
Ypage 350). The current pressures are
saved as new reference values. As a result, a
warning message will appear if the tire pres-
sure drops significantly.
The tire pressure monitor does not warn you
of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(
Ypage 343).
The tire pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tire is penetrated by a foreign object. In the
event of a sudden loss of pressure, bring the
vehicle to a halt by braking carefully. Avoid
abrupt steering movements.
The tire pressure monitor has a yellow warn-
ing lamp in the instrument cluster for indicat-
ing pressure loss or a malfunction. Whet her
t

he warning lamp flashes or lights up indi-
cates whether a tire pressure is too low or the
tire pressure monitor is malfunctioning:
Rif the warning lamp is lit continuously, the
tire pressure on one or more tires is signif-
icantly too low. The tire pressure monitor is not malfunctioning.
Rif 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, a message
appears in the multifunction display. Observe
the information on display messages
(
Ypage 258).
It may take up to ten minutes for a malfunc-
tion of the tire pressure monitor to be indica-
ted. A malfunction will be indicated by the tire
pressure warning lamp flashing for approx-
imately one minute and then remaining lit.
When the malfunction has been rectified, the
tire pressure warning lamp goes out after a
few minutes of driving.
The tire pressure values indicated by the on-
board computer may differ from those meas-
ured at a gas station with a pressure gauge.
The tire pressures shown by the on-board
Tire pressure349
Wheels and tires
Z

computer refer to those measured at sea
level. At high altitudes, the tire pressure val-
ues 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 interference from radio trans-
mitting equipment (e.g. radio headphones,
two-way radios) that may be being operated
in or near the vehicle.
Checking the tire pressure electroni-
cally
XMake sure that the SmartKey is in position
2in the ignition lock (
Ypage 149).
XPress =or; on the steering wheel
to select the Serv.
menu.
XPress the9or: button to select
Tire Pressure
.
XPress the abutton.
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 a few
minutesmessage is shown.
After a teach-in process, the tire pressure
monitor automatically detects new wheels or
new sensors. As long as a clear allocation of
the tire pressure value to the individual
wheels is not possible, the Tire Pressure
Monitor Activemessage is shown instead
of the tire pressure display. The tire pressures are already being monitored.
Tire pressure monitor warning mes-
sages
If the tire pressure monitor detects a pressure
loss in one or more tires, a warning message
is shown in the multifunction display. The yel-
low tire pressure warning lamp then lights up.
RIf the Please Correct Tire Pressure
message appears in the multifunction dis-
play, the tire pressure in at least one tire is too low. The tire pressure must be correc-
ted when the opportunity arises.
RIf the
Check Tire Pressuremessage
appears in the multifunction display, the
tire pressure in one or more tires has drop-
ped significantly. The tires must be
checked.
RIf the Tire Pressure Warning Tire
Failuremessage appears in the multi-
function display, 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
(
Ypage 258).
If the wheel positions on the vehicle are rota-
ted, the tire pressures may be displayed for
the wrong positions for a short time. This is
rectified after a few minutes of driving, and
the tire pressures are displayed for the cor-
rect positions.
Restarting the tire pressure monitor
When you restart the tire pressure monitor, all
existing warning messages are deleted and
the warning lamps go out. The monitor uses
the currently set tire pressures as the refer-
ence values for monitoring. In most cases, the
tire pressure monitor will automatically
detect the new reference values after you
have changed the tire pressure. However, you
can also define reference values manually as described here. The tire pressure monitor
then monitors the new tire pressure values.
XSet the tire pressure to the value recom-
mended for the corresponding driving sit-
uation on the Tire and Loading Information
placard on the driver's side
B-pillar (
Ypage 343).
You can find more tire pressure values for
various operating conditions in the tire
pressure table inside the fuel filler flap
(
Ypage 170).
XMake sure that the tire pressure is correct
on all four wheels.
350Tire pressure
Wheels and tires

XMake sure that the SmartKey is in position2 in the ignition lock (
Ypage 149).
XPress =or; on the steering wheel
to select the Serv.
menu.
XPress the9or: button to select
Tire Pressure
.
XPress the abutton.
The multifunction display shows the cur-
rent tire pressure for each tire or the Tire
pressure will be displayed after
driving a few minutesmessage.
XPress the:button.
The multifunction display shows the Use
CurrentPressuresasNewReference
Valuesmessage.
If you wish to confirm the restart:
XPress the abutton.
The Tire Press. Monitor Restarted
message appears in the multifunction dis-
play.
After driving for a few minutes, the system
checks whether the current tire pressures
are within the specified range. The new tire
pressures are then accepted as reference
values and monitored.
If you wish to cancel the restart:
XPress the %button.
The tire pressure values stored at the last
restart will continue to be monitored.
Radio type approval for the tire pres-
sure monitor
CountryRadio type approval number
USAFCC ID: MRXMW2433A
FCC ID: MRXGG4
FCC ID: MRXMC34MA4
CanadaIC: 2546A-MW2433A
IC: 2546A-GG4
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
the maximum possible load.
(1) The Tire and Loading Information placard is on the B-pillar on the driver's side. The
Tire and Loading Information placard
shows the maximum permissible number
of occupants and the maximum permis-
sible vehicle load. It also contains details
of the tire sizes and corresponding pres-
sures for tires mounted at the factory.
(2) The vehicle identification plate is on the B-pillar on the driver's side. The vehicle
identification plate informs you of the
gross vehicle weight rating. It is made up
of the vehicle weight, all vehicle occu-
pants, the fuel and the cargo. You can
also find information about the maximum
gross axle weight rating on the front and
rear axle.
The maximum gross axle weight rating is
the maximum weight that can be carried
by one axle (front or rear axle). Never
exceed the maximum load or the maxi-
mum gross axle weight rating for the
front or rear axle.
Loading the vehicle351
Wheels and tires
Z

Example:
RTreadwear grade:200
RTraction grade:AA
RTemperature grade: A
All passenger car tires must conform to the
statutory safety requirements in addition to
these grades.
iThe actual values for tires are vehicle-
specific and may deviate from the values in
the illustration.
Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified
U.S. government course. For example, a tire
graded 150 would wear one and one-half
times as well on the government course as a
tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use, how-
ever, and may depart significantly from the
norm due to variations in driving habits, ser-
vice practices and differences in road char-
acteristics and climate.
Traction
GWARNING
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration, cor-
nering, hydroplaning, or peak traction char-
acteristics.
!Avoid wheelspin. This can lead to damage
to the drive train.
The traction grades – from highest to lowest –
are AA, A, B and C. Those grades represent
the tire's ability to stop on wet pavement as
measured under controlled conditions on
specified government test surfaces of asphalt
and concrete. A tire marked C may have poor
traction performance. The safe speed on a wet, snow covered or icy
road is always lower than on dry road surfa-
ces.
You should pay special attention to road con-
ditions when temperatures are around freez-
ing point.
Mercedes-Benz recommends a minimum
tread depth of
ãin (4 mm) on all four winter
tires. Observe the legally required minimum
tire tread depth (
Ypage 341). Winter tires can
reduce the braking distance on snow-covered
surfaces in comparison with summer tires.
The braking distance is still much further than
on surfaces that are not icy or covered with
snow. Take appropri ate ca
re when driving.
Further information on winter tires (M+S
tires) (
Ypage 342).
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
the generation of heat and its ability to dissi-
pate heat when tested under controlled con-
ditions on a specified indoor laboratory test
wheel. Sustained high temperature can cause
the material of the tire to degenerate and
reduce tire life, and excessive temperature
can lead to sudden tire failure. The grade C
corresponds to a level of performance which
all passenger car tires must meet under the
Federal Motor Vehicle Safety Standard No.
109. Grades B and A represent higher levels
of performance on the laboratory test wheel
than the minimum required by law.
356All about wheels an d tires
Wheels and tires

Tire labeling
Overview
:Uniform Tire Quality Grading Standards
(
Ypage 361)
;Department of Transportation, Tire Iden-
tification Number (
Ypage 360)
=Maximum load rating (Ypage 359)
?Maximum tire pressures (Ypage 346)
AManufacturer
BTire material (Ypage 360)
CTire size designation, load-bearing capa-
city and speed rating (
Ypage 357)
DLoad index (Ypage 359)
ETire name
The markings described above are on the tire
in addition to the tire name (sales designa-
tion) and the manufacturer's name.
iTire data is vehicle-specific and may devi-
ate from the data in the example.
Tire size designation, load-bearing
capacity and speed rating
GWARNING
Exceeding the stated tire load-bearing capa-
city and the approved maximum speed could
lead to tire damage or the tire bursting. There is a risk of accident.
Therefore, only use tire types and sizes
approved for your vehicle model. Observe the
tire load rating and speed rating required for
your vehicle.
:Tire width
;Nominal aspect ratio in %
=Tire code
?Rim diameter
ALoad bearing index
BSpeed rating
General: depending on the manufacturer's
standards, the size imprinted in the tire wall
may not contain any letters or may contain
one letter that precedes the size description.
If there is no letter preceding the size descrip-
tion (as shown above): these are passenger
vehicle tires according to European manufac-
turing standards.
If "P" precedes the size description: these are
passenger vehicle tires according to U.S.
manufacturing standards.
If "LT" precedes the size description: these
are light truck tires according to U.S. manu-
facturing standards.
If "T" precedes the size description: compactemergency wheels with high tire pressure
that are only designed for temporary use in an
emergency.
Tire width: tire width:shows the nominal
tire width in millimeters.
Aspect ratio: aspect ratio;is the size ratio
between the tire height and tire width and is
shown in percent. The aspect ratio is calcu-
All about wheels an d tires357
Wheels and tires
Z

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 322) contains information and notes
on how to deal with a flat tire. Information on driving with MOExtended tires in the event of
a flat tire can be found under "MOExtended
tires (tires with run-flat characteristics"
(
Ypage 323).
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 loca-
ted in the wheel.
Tire-mounting tools should not be used
near the valve. This could damage the elec- tronic components.
Only have tires changed at a qualified spe-
cialist workshop.
Observe the instructions and safety notes in
the "Changing a wheel" section (
Ypage 363).
The wear patterns on the front and rear tires
differ, depending on the operating conditions.
Rotate the wheels before a clear wear pattern has formed on the tires. Front tires typically
wear more on the shoulders and the rear tires
in the center.
On vehicles that have the same size front and
rear wheels, you can rotate the wheels
according to the intervals in the tire manu-
facturer's warranty book in your vehicle docu-
ments. If no warranty book is available, the
tires should be rotated every 3,000 to
6,000 miles (5,000 to 10,000 km). Depending
on tire wear, this may be required earlier. Do
not change the direction of wheel rotation.
Clean the contact surfaces of the wheel and
the brake disc thoroughly every time a wheel
is rotated. Check the tire pressure and, if nec-
essary, restart the tire pressure loss warning
system or the tire pressure monitor.
Direction of rotation
Tires with a specified direction of rotation
have additional benefits, e.g. if there is a risk of hydroplaning. These advantages can only
be gained if the tires are installed correspond-
ing to the direction of rotation.
An arrow on the sidewall of the tire indicates its correct direction of rotation.
Storing wheels
Store wheels that are not being used in a cool,
dry and preferably dark place. Protect the
tires from oil, grease, gasoline and diesel.
Mounting a wheel
Preparing the vehicle
XStop the vehicle on solid, non-slippery and
level ground.
XApply the electric parking brake manually.
XBring the front wheels into the straight-
ahead position.
XShift the transmission to position P.
XSwitch off the engine.
Changing a wheel363
Wheels and tires
Z

XVehicles without KEYLESS-GO:remove
the SmartKey from the ignition lock.
XVehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: open the driver's
door.
The on-board electronics now have status
0 . This is the same as the SmartKey having
been removed.
XVehicles with KEYLESS-GO start-func-
tion or KEYLESS-GO: remove the Start/
Stop button from the ignition lock
(
Ypage 149).
XMake sure that the engine cannot be star-
ted via your smartphone (
Ypage 171).
XIf included in the vehicle equipment,
remove the tire-change tool kit from the
vehicle.
XSafeguard the vehicle against rolling away
(
Ypage 171).
Securing the vehicle to prevent it from
rolling away
If your vehicle is equipped with a wheel chock,
it can be found in the tire-change tool kit
(
Ypage 322).
The folding wheel chock is an additional
safety measure to prevent the vehicle from
rolling away, for example when changing a
wheel.
XFold both plates upwards :.
XFold out lower plate;.
XGuide the lugs on the lower plate fully into
the openings in base plate =.
XPlace chocks or other suitable items under
the front and rear of the wheel that is diag-
onally opposite the wheel you wish to
change.
Raising the vehicle
GWARNING
If you do not position the jack correctly at the
appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle.
!The jack is designed exclusively for jack-
ing up the vehicle at the jacking points.
Otherwise, your vehicle could be damaged.
Observe the following when raising the
vehicle:
RTo raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If used incor-
rectly, the jack could tip over with the vehi- cle raised.
RThe jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It must not be used for
performing maintenance work under the
vehicle.
RAvoid changing the wheel on uphill and
downhill slopes.
364Changing a wheel
Wheels and tires

XTurn ratchet wrench?until jack =sits
completely on jacking point ;and the
base of the jack lies evenly on the ground.
XTurn ratchet wrench ?until the tire is
raised a maximum of 1.2 in (3 cm) from the ground.
Removing a wheel
!Do not place wheel bolts in sand or on a
dirty surface. The bolt and wheel hub
threads could otherwise be damaged when
you screw them in.
XUnscrew the wheel bolts.
XRemove the wheel.
Mounting a new wheel
GWARNING
Oiled or greased wheel bolts or damaged
wheel bolts/hub threads can cause the wheel 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 and
safety notes in the "Changing a wheel" sec-
tion (
Ypage 363).
Only use wheel bolts that have been designed for the wheel and the vehicle. For safety rea-
sons, Mercedes-Benz recommends that you
only use wheel bolts which have been
approved for Mercedes-Benz vehicles and the
respective wheel.
!To prevent damage to the paintwork, hold
the wheel securely against the wheel hub
while screwing in the first wheel bolt.
XClean the wheel and wheel hub contact
surfaces.
XPlace the new wheel on the wheel hub and push it on.
XTighten the wheel bolts until they are fin-
ger-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 hexagon
nut of the jack so that the letters ABare
visible.
XTurn the ratchet wrench until the vehicle is
once again standing firmly on the ground.
XPlace the jack to one side.
366Changing a wheel
Wheels and tires

XTighten the wheel bolts evenly in a cross-
wise pattern in the sequence indicated (:
to A). The specified tightening torque is
96 lb-ft (130 Nm).
XTurn the jack back to its initial position.
XStow the jack and the rest of the vehicle
tools in the vehicle again.
XCheck the tire pressure of the newly moun-
ted wheel and adjust it if necessary.
Observe the recommended tire pressure
(
Ypage 343).
When you are driving with the collapsible
spare wheel mounted, the tire pressure loss
warning system or the tire pressure monitor
cannot function reliably. Only restart the tire
pressure loss warning system or tire pressure
monitor when the defective wheel has been
replaced with a new wheel.
Vehicles with a tire pressure control sys-
tem: all installed wheels must be equipped
with functioning sensors.
Wheel and tire combinations
General notes
!
For safety reasons, Mercedes-Benz rec-
ommends that you only use tires and
wheels which have been approved by
Mercedes-Benz specifically for your vehi-
cle. These tires have been specially adapted for
use with the control systems, such as ABS
or ESP
®, and are marked as follows:
RMO = Mercedes-Benz Original
RMOE = Mercedes-Benz Original Extended
(tires featuring run-flat characteristics)
RMO1 = Mercedes-Benz Original (only cer-
tain AMG tires)
Mercedes-Benz Original Extended tires
may only be used on wheels that have been
specifically approved by Mercedes-Benz.
Only use tires, wheels or accessories tes-
ted and approved by Mercedes-Benz. Cer-
tain characteristics, e.g. handling, vehicle
noise emissions or fuel consumption, may
otherwise be adversely affected. In addi-
tion, when driving with a load, tire dimen-
sion variations could cause the tires to
come into contact with the bodywork and
axle components. This could result in dam-
age to the tires or the vehicle.
Mercedes-Benz accepts no liability for
damage resulting from the use of tires,
wheels or accessories other than those tes-
ted and approved.
Information on tires, wheels and approved
combinations can be obtained from any
qualified specialist workshop.
!Retreaded tires are neither tested nor rec-
ommended by Mercedes-Benz, since pre-
vious damage cannot always be detected
on retreaded tires. As a result, Mercedes-
Benz cannot guarantee vehicle safety if
retreaded tires are mounted. Do not mount
used tires if you have no information about
their previous usage.
Overview of abbreviations used in the follow-
ing tire tables:
RBA: both axles
RFA: front axle
RRA: rear axle
Wheel and tire combinations367
Wheels and tires
Z