TPMS MERCEDES-BENZ CLS 2018 Owners Manual

Tires Warning/
indicator
lamp Q Signal type
Possible causes/consequences and P Solutions
w
Q The yellow combination low tire pressure telltale/TPMS malfunction telltale for
the TPMS (pressure loss or malfunction) is lit.
The tire pressure monitor has detected a loss of pressure in at least one of the tires.
G WARNING
Tire pressures that are too low pose 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 trac-
tion. 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 141).X
Observe the additional display messages in the multifunction display. X
Check the tires and, if necessary, follow the instructions for a flat tire
( Y
page 278). X
Check the tire pressure ( Y
page 299).X
If necessary, correct the tire pressure.
w
Q 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 immediately.Warning and indicator lamps in the instrument cluster 235
On-board computer and displays Z

For information on the message display, refer to
the "Checking the tire pressure electronically"
section ( Y
page 301).
Important safety notes
G WARNING
Each tire, including the spare (if provided),
should be checked at least once every two
weeks when cold and inflated to the pressure
recommended by the vehicle manufacturer
on the Tire and Loading Information placard
on the driver's door B-pillar or the tire pres-
sure label on the inside of the fuel filler flap. If
your vehicle has tires of a different size than
the size indicated on the Tire and Loading
Information placard or, if available, the tire
pressure label, you should determine the
proper tire pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring
system (TPMS) that illuminates a low tire pres-
sure telltale when one or more of your tires
are significantly underinflated. Accordingly,
when the low tire pressure telltale lights up,
you should stop and check your tires as soon
as possible, and inflate them to the proper
pressure. Driving on a significantly underin-
flated tire causes the tire to overheat and can
lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle's
handling and stopping ability. Please note that
the TPMS is not a substitute for proper tire
maintenance, and it is the driver's responsi-
bility to maintain correct tire pressure, even if
underinflation has not reached the level to
trigger illumination of the TPMS low tire pres-
sure 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 sys-
tem detects a malfunction, the warning lamp
will flash for approximately a minute and then
remain continuously illuminated. This
sequence will be repeated every time the vehi-
cle is started as long as the malfunction
exists. When the malfunction indicator is illu-
minated, the system may not be able to detect
or signal low tire pressure as intended.
TPMS malfunctions may occur for a variety of
reasons, including the installation of incom-
patible replacement or alternate tires or
wheels on the vehicle that prevent the TPMS
from functioning properly. Always check the
TPMS malfunction telltale after 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 295). 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
pre ssure moni tor after adjusting the pressure of
the
cold tires ( Y
page 302). The current pres-
sures 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 295).
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
movements.300
Tire pressure
Wheels and tires