Checking tire pressures manually
To determine and set the correct tire pres-
sure, proceed as follows: XRemove 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 to
the recommended value on the Tire and
Loading Information placard or the tire
pressure table ( Ypage 305).
X If the tire pressure is too low, increase the
tire pressure to the recommended value.
X If the tire pressure is too high, release air.
To do so, press 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 checker.
X Screw the valve cap onto the valve.
X Repeat these steps for the other tires.
Tire pressure loss warning system
General notes
While the vehicle is in motion, the tire pres-
sure 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 dis- play.
You can recognize the tire pressure loss warn-
ing in the multifunction display in the
Serv.
menu, by theRunFlatIndicatorActive
Press 'OK' to Restartmessage. Further
information on displaying this message can
be found under "Restarting the tire pressure
loss warning system" ( Ypage 309).
Important safety notes
The tire pressure warning system does not
warn you of an incorrectly set tire pressure.
Observe the notes on the recommended tire
pressure ( Ypage 305).
The tire pressure loss warning does not
replace the need to regularly check the tire
pressure. An even loss of pressure on several tires at the same time cannot be detected bythe tire pressure loss warning system.
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 maneuvers.
The function of the tire pressure loss warning
system is limited or delayed if:
R snow chains are mounted on 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 (cor-
nering 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 warn-
ing 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 pressure can be
found on the Tire and Loading Information
placard on the B-pillar. Additionally, a tire
pressure table is attached to the fuel filler
flap. The tire pressure loss warning system
can only give reliable warnings if you have
Tire pressure309
Wheels and tires
Z
Observe the following when raising the vehicle:
R To 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.
R The jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suited for per-
forming maintenance work under the vehi-
cle.
R Avoid changing the wheel on uphill and
downhill slopes.
R Before raising the vehicle, secure it from
rolling away by applying the parking brake
and inserting wheel chocks. Do not disen-
gage the parking brake while the vehicle is
raised.
R The jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, flat, load-bearing underlay must be
used. On a slippery surface, a non-slip
underlay must be used, e.g. rubber mats.
R Do not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacity due to the restrictedheight.
R Make sure that the distance between the
underside of the tires and the ground does
not exceed 1.2 in (3 cm).
R Never place your hands and feet under the
raised vehicle.
R Do not lie under the vehicle.
R Do not start the engine when the vehicle is
raised.
R Never open or close a door or the tailgate
when the vehicle is raised.
R Make sure that no persons are present in
the vehicle when the vehicle is raised.
XUsing lug wrench :, loosen the bolts on
the wheel you wish to change by about one full turn. Do not unscrew the bolts com- pletely.
Jacking points
The jacking points are located just behind the front wheel housings and just in front of the
rear wheel housings (arrows).
X Take ratchet wrench ?out of the vehicle
tool kit and place it on the hexagon nut of jack =so that the letters AUFare visible.
X Position jack =at jacking point ;.
324Changing a wheel
Wheels and tires