Problem Possible causes/consequences and
M SolutionsX
Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and add coolant, observing the warning
notes ( Y page 300).
X If you need to add coolant more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X At coolant temperatures under 248 ‡ (120 †), drive to the next
qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic. Driving systems
Problem Possible causes/consequences and
M Solutions·
The red distance
warning lamp lights up
while the vehicle is in
motion.
A warning tone
also sounds. You are approaching a vehicle or a stationary obstacle in your line
of travel at too high a speed.
X
Be prepared to brake immediately.
X Pay careful attention to the traffic situation. You may have to
brake or take evasive action.
Further information on DISTRONIC PLUS ( Y page 167).
Further information on PRE-SAFE ®
Brake (Y page 69). 266
Warning and indicator lamps in the instrument cluster
On-board computer and displays
Tires
Problem Possible causes/consequences and
M Solutionsh
USA only:
The
yellow tire pressure
monitor warning lamp
(pressure loss/
malfunction) is lit.
Canada only:
The yellow tire pressure
monitor warning lamp
(pressure loss) is lit. The tire pressure monitor has detected a loss of pressure in at
least one of the tires.
G WARNING
With tire pressures which are too low, there is a risk of the
following hazards:
R they may burst, especially as the load and vehicle speed
increase.
R they
may wear excessively and/or unevenly, which may greatly
impair tire traction.
R the driving characteristics, as well as steering and braking, may
be greatly impaired.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
maneuvers.
Pay attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away ( Y page 157).
X Observe the additional display messages in the multifunction
display.
X If there is a flat tire, inspect the tires ( Y page 313).
X Check the tire pressure (Y page 334).
X If necessary, correct the tire pressure. h
USA only:
The
yellow tire pressure
monitor warning lamp
(pressure loss/
malfunction) flashes for
approximately one
minute and then
remains lit. The tire pressure monitor is faulty.
G WARNING
The system is possibly unable to recognize or register low tire
pressure.
There is a risk of an accident.
X Observe the additional display messages in the multifunction
display.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
267
On-board computer and displays Z
Some tire pressure tables show only the rim
diameters instead of the full tire size, e.g.
R18. The rim diameter is part of the tire size
and can be found on the tire sidewall
(Y page 342).
If the tire pressures have been set to the
lower values for lighter loads and/or lower
road speeds, the pressures should be reset
to the higher values:
R
if you want to drive with an increased load
and/or
R if you want to drive at higher road speeds.
i The tire pressures for increased loads
and/or higher road speeds, shown in the
tire pressure table, may have a negative
effect on driving comfort.
If the tire pressure is not set correctly, this
can
lead to an excessive build up of heat and
a sudden loss of pressure.
For more information, contact a qualified
specialist workshop. Important notes on tire pressure
G
WARNING
If the tire pressure drops repeatedly, the
wheel, valve or tire may be damaged. Tire
pressure that is too low may result in a tire
blow-out. There is a risk of an accident.
R Check the tire for foreign objects.
R Check
whether the wheel is losing air or the
valve is leaking. If you are unable to rectify the damage,
contact a qualified specialist workshop.
G
WARNING
If you fit unsuitable accessories onto tire
valves,
the tire valves may be overloaded and
malfunction, which can cause tire pressure
loss. Due to their design, retrofitted tire
pressure monitors keep the tire valve open.
This can also result in tire pressure loss. There
is a risk of an accident.
Only screw the standard valve cap or other
valve caps approved by Mercedes-Benz for
your vehicle onto the tire valve.
Use a suitable pressure gauge to check the
tire pressure. The outer appearance of a tire
does not permit any reliable conclusion about
the tire pressure. On vehicles equipped with
the electronic tire pressure monitoring
system, the tire pressure can be checked
using the on-board computer.
The tire temperature and pressure increase
when the vehicle is in motion. This is
dependent on the driving speed and the load.
Therefore, you should only correct tire
pressures when the tires are cold.
The tires are cold:
R if the vehicle has been parked without
direct sunlight on the tires for at least three
hours and
R if the vehicle has been driven for less than
1 mile (1.6 km).
The tire temperature changes depending on
the outside temperature, the vehicle speed
and the tire load. If the tire temperature
changes by 18 ‡ (10 †), the tire pressure
changes by approximately 10 kPa (0.1 bar/
1.5 psi). Take this into account when
checking the pressure of warm tires. Only
correct the tire pressure if it is too low for the
current operating conditions. If you check the
tire pressure when the tires are warm, the
resulting value will be higher than if the tires
were cold. This is normal. Do not reduce the
tire pressure to the value specified for cold Tire pressure
331
Wheels and tires Z
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
(Y page 329). Note that the correct tire
pressure 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 adjusting the pressure of the
cold tires (Y page 336). The current
pressures
are saved as new reference values.
As a result, a warning message will appear if
the tire pressure drops significantly.
The tire pressure monitor does not warn you
of an incorrectly set tire pressure. Observe
the notes on the recommended tire pressure
(Y page 329).
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.
If a tire pressure monitor system is installed,
the vehicle's wheels have sensors installed
that monitor the tire pressures in all four tires.
The tire pressure monitor warns you if the
pressure drops in one or more of the tires. The
tire pressure monitor only functions if the
correct sensors are installed on all wheels.
The tire pressure monitor has a yellow
warning lamp in the instrument cluster for
indicating pressure loss/malfunctions (USA)
or pressure loss (Canada). Whether the
warning lamp flashes or lights up indicates
whether a tire pressure is too low or the tire
pressure monitor is malfunctioning:
R if the warning lamp is lit continuously, the
tire pressure on one or more tires is significantly too low. The tire pressure
monitor is not malfunctioning.
R USA only: if the warning lamp flashes for
around a minute and then remains lit
constantly, the tire pressure monitor is
malfunctioning.
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 multifunction display.
USA only: if there is a malfunction with the
tire pressure monitor it can take more than
ten minutes until the malfunction is shown by
the tire pressure warning lamp flashing for
approximately one minute and then lighting
up continuously. 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
measured 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
transmitting equipment (e.g. radio
headphones, two-way radios) that may be
being operated in or near the vehicle.
i USA only:
This device complies with part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause interference,
and
2. this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment. Tire pressure
335
Wheels and tires Z