lights MERCEDES-BENZ METRIS 2020 MY20 Operator’s Manual

For further information on displaying the cur-
rent tire pressures, refer to "Checking the tire
pressure electronically"
(Y page 287).
Important safety notes G
WARNING
Risk of accident due to incorrect tire
pressure
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recommen-
ded by the vehicle manufacturer on the vehi-
cle placard or tire inflation pressure label. (If
your vehicle has tires of a different size than
the size indicated on the vehicle placard or
the tire inflation pressure label, you should
determine the proper tire inflation 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 is significantly under-inflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your
tires as soon as possible, and inflate them to
the proper pressure. Driving on a signifi-
cantly under-inflated tire causes the tire to
overheat and can lead to tire failure. Under-
inflation also reduces fuel efficiency and tire
tread life, and may affect the vehicle's han-
dling and stopping ability.
Please note that the TPMS is not a substi-
tute for proper tire maintenance, and it is
the driver's responsibility to maintain cor-
rect tire pressure, even if under-inflation 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 telltale
will flash for approximately one minute and
then remain continuously illuminated. This sequence will continue upon subsequent
vehicle start-ups as long as the malfunction
exists.
When the malfunction indicator is illumina-
ted, the system may not be able to detect or
signal low tire pressure as intended. TPMS
malfunctions may occur for a variety of rea-
sons, including the installation of replace-
ment or alternate tires or wheels on the
vehicle that prevent the TPMS from func-
tioning properly.
Always check the TPMS malfunction telltale
after replacing one or more tires or wheels
on your vehicle to ensure that the replace-
ment 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 the recommended cold tire pres-
sure suitable for the operating conditions
(Y page
282).
Note that the correct tire pressure for the cur-
rent operating conditions must first be pro-
gramed into the tire pressure monitor. If a sub-
stantial pressure loss occurs, the warning
threshold for the warning message is aligned
to the taught-in reference values. Restart the
tire pressure monitor after adjusting the cold
tire pressure ( Y page 288). The current pres-
sures are saved as new reference values. This
will ensure that a warning message will only
appear if the tire pressure drops significantly.
The tire pressure monitor does not warn you if
a tire pressure is incorrect. Observe the notes
on the recommended tire pressure
(Y page 282).
The tire pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. following
penetration by a foreign object. In this event,
brake the vehicle until it comes to a standstill.
Avoid sudden steering movements.
The tire pressure monitor has a yellow h
warning lamp in the instrument cluster for indi-
cating pressure loss/malfunctions (USA) or
pressure loss (Canada). Depending on how the
warning lamp flashes or lights up, an underin-
flated tire or a malfunction in the tire pressure
monitor is displayed:
R if the h warning lamp is lit continuously,
the tire pressure on one or more tires is sig- 286
Tire pressure
Wheels and tires

nificantly too low. The tire pressure monitor
is not malfunctioning.
R USA only: if the h warning lamp flashes
for
60 seconds and then remains lit con-
stantly, the tire pressure monitor is malfunc-
tioning.
The display also shows a message:
R on vehicles without steering wheel buttons
(Y page 207)
R on vehicles with steering wheel buttons
(Y page 224)
USA only: if the tire pressure monitor is mal-
functioning, it may be more than ten minutes
before the malfunction is shown. The h tire
pressure warning lamp flashes for 60 seconds
and then remains lit. When the malfunction
has been rectified, the h 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
computer refer to those measured at sea level.
At high altitudes, the tire pressure values indi-
cated by a pressure gauge are higher than
those shown by the on-board computer. In this
case, do not reduce the tire pressures.
If radio transmitting equipment (e.g. wireless
headphones, two-way radios) is operated
inside the vehicle or in the vicinity of the vehi-
cle, this can interfere with the operation of the
tire pressure monitor.
Checking the tire pressure electroni-
cally on vehicles with steering wheel
buttons You can only check the tire pressure electroni-
cally on vehicles with steering wheel buttons.
Using the steering wheel buttons
X Turn the key to position 2 in the ignition
lock.
X Press the = or ; button to select the
Service menu.
X Use the 9 or : button to select
Tire Pressure.
X Press a to confirm.
The current tire pressure of each wheel is
shown in the display. If the vehicle has been parked for over
20 minutes
, the Tire pressure will be
displayed after driving a few minutes
message appears.
After a teach-in period, the tire pressure moni-
tor 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
Active message 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 loss in
pressure in one or more tires, a warning mes-
sage is shown in the display. The h warn-
ing lamp lights up.
Vehicles without steering wheel buttons
R If the Correct Tire Pressure message is
shown in the display, the tire pressure in at
least one tire is too low. The tire pressure
must be corrected at the next opportunity.
R If the Check Tire Pressure Soon mes-
sage is shown in the display, the tire pres-
sure in one or more tires has dropped signif-
icantly. The tires must be checked.
R If the Warning Tire Malfunc. message is
shown in the display, the tire pressure in
one or more tires has dropped suddenly.
The tires must be checked.
Vehicles with steering wheel buttons
R If the Adjust Tire Pressure message is
shown in the display, the tire pressure in at
least one tire is too low. The tire pressure
must be corrected at the next opportunity.
R If the Check Tires message is shown in the
display, the tire pressure in one or more
tires has dropped significantly. The tires
must be checked.
R If the Warning Tire Malfunction mes-
sage is shown in the display, the tire pres-
sure in one or more tires has dropped sud-
denly. The tires must be checked. Tire pressure
287
Wheels and tires Z