Checking tire pressures manually
To determine and set the correct tire
pressure, proceed as follows:
X
Remove the valve cap of the tire that is to
be checked.
X Press the tire pressure gauge securely onto
the valve.
X Read the tire pressure and compare it with
the recommended value on the Tire and
Loading Information placard on the
B-pillar on the
driver's side of your vehicle.
X If necessary, increase the tire pressure to
the recommended value ( Y page 301).
X If the tire pressure is too high, release air
by pressing down
the metal pin in the valve
using the tip of a pen, for example. Then,
check the tire pressure again using the tire
pressure gauge.
X Screw the valve cap onto the valve.
X Repeat these steps for the other tires. Tire pressure loss warning system
Important safety notes While the vehicle is in motion, the tire
pressure loss warning system monitors the
set
tire
pressure
using the rotational speed of
the wheels. This enables the system to detect
significant pressure loss in a tire. If the speed
of rotation of a wheel changes as a result of
a loss of pressure, a corresponding warning
message will appear in the multifunction
display.
The tire pressure warning system does not
warn you of an incorrectly set tire pressure.
Observe the notes on the recommended tire
pressure ( Y page 301).
The tire pressure loss warning system does
not replace the need to regularly check your
vehicle's tire pressures, since an even loss of
pressure on several tires at the same time
cannot be detected by the tire pressure loss
warning system. The tire pressure loss warning system 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 maneuvers.
The function of the tire pressure loss warning
system is limited or delayed if:
R snow chains are mounted to your vehicle's
tires.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style
(cornering at high speeds or driving with
high rates of acceleration).
R you are driving with a heavy load (in the
vehicle or on the roof).
Restarting the tire pressure loss
warning system Restart the tire pressure loss warning system
if you have:
R
changed the tire pressure
R changed the wheels or tires
R mounted new wheels or tires
X Before restarting, make sure that the tire
pressures are set properly on all four tires
for the respective operating conditions.
The recommended tire pressures can be
found in the table on the fuel filler flap.
The tire pressure loss warning system can
only give reliable warnings if you have set
the correct tire
pressure. If an incorrect tire
pressure is set, these incorrect values will
be monitored.
X Observe the notes on tire pressure
(Y page 301).
X Make sure that the SmartKey is in
position 2 (Y page 135)
in the ignition lock. Tire pressure
305
Wheels and tires Z
ProCarManuals.com
Tires
Summer tires Alloy wheels V1
BA
225/40 R18 92 W XL MOExtended
8, 9 7.5 J x 18 H2
Wheel offset: 2.05 in (52 mm) #
All-weather tires Alloy wheels V1
BA
225/45 R17 91 H M+SMOExtended
8, 9 7.5 J x 17 H2
Wheel offset: 2.07 in (52.5 mm
) #
Winter tires Alloy wheels V1
BA 205/50 R17 93 H XL M+S
i 6.5 J x 17 H2
Wheel offset: 1.93 in (49 mm) #
BA 205/50 R17 93 H XL
M+SiMOExtended
9 6.5 J x 17 H2
Wheel offset: 1.93 in (49 mm) #
Emergency spare wheel
Important safety notes
G
WARNING
The wheel or tire size as well as the tire type
of the spare
wheel or emergency spare wheel
and the wheel to be replaced may differ.
Mounting an emergency spare wheel may
severely impair the driving characteristics.
There is a risk of an accident.
To avoid hazardous situations:
R adapt your driving style accordingly and
drive carefully.
R never mount more than one spare wheel or
emergency spare wheel that differs in size.
R only use a spare wheel or emergency spare
wheel of a different size briefly.
R do not switch ESP ®
off.
R have a spare wheel or emergency spare
wheel of a different size replaced at the
nearest qualified specialist workshop. Observe that the wheel and tire dimensions
as well as the tire type must be correct.
When using an emergency spare wheel or
spare wheel of a different size, you must not
exceed the maximum speed of 50 mph
(80 km/h).
Snow chains must not be mounted on
emergency spare wheels. General notes
You should regularly check the pressure of
the emergency spare
wheel, particularly prior
to long trips, and correct the pressure as
necessary ( Y page 301). The value on the
wheel or as given in the "Technical data"
section ( Y page 323) is valid.
i When you are driving with the emergency
spare wheel mounted, the tire pressure
loss warning system cannot function
reliably. Only restart the tire pressure loss
8 Use of snow chains is not permitted. Observe the notes in the "Snow chains" section.
9 MOExtended tires (tires with run-flat characteristics) only in conjunction with activated tire pressure loss
warning. Emergency spare wheel
325
Wheels and tires Z
ProCarManuals.com