the information on display messages
(
Y
page 306).
It may take up to ten minutes for a malfunction
of the tire pressure monitor to be indicated. A
malfunction will be indicated by the tire pres-
sure warning lamp flashing for approximately
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 computer
refer to those measured at sea level. At high
altitudes, the tire pressure values 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 transmit-
ting equipment (e.g. radio headphones, two-way
radios) that may be being operated in or near the
vehicle.
Checking the tire pressure electroni-
cally
X
Make sure that the SmartKey is in position 2
in the ignition lock (
Y
page 162).
X
Use
ò
on the steering wheel to call up the
list of menus.
X
Press
9
or
:
on the steering wheel to
select the
Service
menu.
X
Press the
a
button.
X
Press
9
or
:
to select
Tire Pres‐
sure
.
X
Press the
a
button.
The current tire pressure of each tire is shown
in the multifunction display.
If the vehicle was parked for longer than
20 minutes, the following message appears:
Tire pressure will be displayed after
driving a few minutes
.
After a teach-in process, the tire pressure mon-
itor 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 pressure
loss in one or more tires, a warning message is
shown in the multifunction display. The yellow
tire pressure warning lamp then lights up.
R
If the
Please Correct Tire Pressure
message appears in the multifunction display,
the tire pressure in at least one tire is too low.
The tire pressure must be corrected when the
opportunity arises.
R
If the
Check Tires
message appears in the
multifunction display, the tire pressure in at
least one tire has dropped significantly. The
tires must be checked.
R
If the
Warning Tire Malfunction
message
appears in the multifunction display, the tire
pressure in at least one tire has dropped sud-
denly. The tires must be checked.
Observe the instructions and safety notes in the
display messages in the "Tires" section
(
Y
page 306).
If the wheel positions on the vehicle are rotated,
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 pres-
sures are displayed for the correct 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 cur-
rently set tire pressures as the reference values
for monitoring. In most cases, the tire pressure
monitor will automatically detect the new refer-
ence values after you have changed the tire
pressure. However, you can also define refer-
ence values manually as described here. The tire
pressure monitor then monitors the new tire
pressure values.
X
Set the tire pressure to the value recommen-
ded for the corresponding driving situation on
the Tire and Loading Information placard on
the driver's side B-pillar (
Y
page 387).
You can find more tire pressure values for
various operating conditions in the tire pres-
sure table inside the fuel filler flap
(
Y
page 387).
X
Make sure that the tire pressure is correct on
all four wheels.
392
Tire pressure
Whee
ls
an
d
tires
