2018 MERCEDES-BENZ S CLASS Owners Manual

R
The tires may we ar exc essively and/or
une ve nl y, which may greatly impair tire
traction. R
The driving ch aracteristics, as we ll as
st eering and braking, may be greatly
impaired.

q
WA RNING Risk of accident caused by
re peated drop in tire pressure
If th e tire pressure drops re peatedl y, th e
wheel, va lv e or tire may be damaged.
Insuf fi cient tire pressure can cause th e tires
to bur st .

The tire pressure ta ble sho ws th e re commended
tire pressure fo r all tires app ro ve d fo r th is ve hi‐
cle. The re commended tire pressures apply fo r
cold tires under va ri ous operating conditions, i.e.
loading and/or speed of th e ve hicle.
If one or more tire sizes precede a tire pressure,
th e tire pressure information fo llowing is only
va lid fo r th ose tire sizes.
The load conditions "partially laden" and "fully
laden" are defined in th e ta ble fo r dif fe re nt num‐
be rs of passengers and amounts of luggage. The
actual number of seats may dif fe r from th is. Some tire pressure ta bles only show th e ri m
diame te r ins te ad of th e comple te tire size, e.g.
R18 . The ri m diame te r is part of th e tire size and
can be fo und on th e tire side wa ll ( →
page 428).
Be sure to also obse rv e th e fo llowing fur th er
re lated subjects: R
No te s on tire pressure ( →
page 41 4)R
Ti re and Loading In fo rm ation placard
( →
page 420) R
Maximum tire pressure ( →
page 428)
Checking tire pressu re s manually

Fu rt her re lated subjects:R
No te s on tire pressure ( →
page 41 4)R
Ti re pressure ta ble ( →
page 41 6)R
Ti re and Loading In fo rm ation placard
( →
page 420)
Ti re pressure moni to ri ng sy st em
Fu nction of th e tire pressure moni to ri ng sys‐
te m
q
DA NG ER Risk of accident due to incor‐
re ct tire pressure
Every tire, including th e spare (if pr ov ided),
should be ch ec ke d when cold at least once a
month and inflated to th e pressure re com‐
mended by th e ve hicle manufacturer (see
Ti re and Loading In fo rm ation placard on th e
B-pillar on th e driver ’s side or th e tire pres‐
sure label on th e inside of th e fuel fi ller fl ap
of yo ur ve hicle). If yo ur ve hicle has tires of a
dif fe re nt size th an th e size indicated on th e
Ti re and Loading In fo rm ation placard or th e tire pressu re ta ble, yo u need to de te rm ine
th e proper tire pressure fo r th ose tires.
As an added saf et y fe ature, yo ur ve hicle has
been equipped with a tire pressure monitor‐
ing sy st em (TPMS) th at illuminates a low tire
pressure indicator lamp when one or more of
yo ur tires are sign if icantly underinflated.
Ac cording ly , if th e low tire pressure indicator
lamp lights up, yo u should st op and ch eck
yo ur tires as soon as possible, and inflate
th em to th e proper pressure. Driving on a
significant ly underinflated tire causes th e tire
to ove rh eat and can lead to tire fa ilure.
Und erinflation also increases fuel consump‐
tion and re duces tire tread life, and may
af fe ct th e ve hicle's handling and braking abil‐
ity. Please no te th at th e TPMS is not a substi‐
tute fo r proper tire maintenance, and it is th e
driver's re sponsibility to maintain cor re ct tire
pressure, ev en if underinflation has not
re ached th e le ve l to trig ge r illumination of
th e TPMS low tire pressure indicator lamp.
Yo ur ve hicle has also been equipped with a
TPMS malfunction indicator to indicate when th e sy st em is not operating properly. The
TPMS malfunction indicator is combined with
th e low tire pressure indicator lamp. When
th e sy st em de te cts a malfunction, th e indica‐
to r lamp will fl ash fo r app ro xima te ly a minute
and th en re main continuously illumina te d.
This sequence will continue upon subsequent
ve hicle st art-ups as long as th e malfunction
ex ists.
When th e malfunction indicator is illumina‐
te d, th e sy st em may not be able to de te ct or
signal low tire pressure as intended. TPMS
malfunctions may occur fo r a va ri et y of re a‐
sons, including th e ins ta llation of incompati‐
ble re placement or alternate tires or wheels
on th e ve hicle th at pr ev ent th e TPMS from
functioning proper ly .
Alw ay s ch eck th e TPMS malfunction wa rn ing
lamp af te r re placing one or more tires or
wheels on yo ur ve hicle to ensure th at th e
re placement or alternate tires and wheels
allow th e TPMS to continue to function prop‐
er ly .41 8
Wheels and tires

The sy st em ch ec ks th e tire pressure and th e tire
te mp erature of th e tires mounted on th e ve hicle
by means of a tire pressu re sensor.
New tire pressure sensor, e.g. in winter tires, are
automatically ta ught-in th e fi rs t time th ey are
driven.
The tire pressure appears in th e multifunction
display ( →
page 24 7).
If th ere is a subs ta ntial pressure loss or if th e
tire te mp erature is exc essive, a wa rn ing will be
given: R
Vi a display messages ( →
page 487).R
Vi a th e w wa rn ing lamp in th e instrument
clus te r ( →
page 51 7) .
It is th e driver's re sponsibility to set th e tire
pressure to th e re commended cold tire pressure
suitable fo r th e operating situation. Set th e tire
pressure fo r cold tires using a tire pressu re
ga uge. No te th at th e cor re ct tire pressure fo r th e
cur re nt operating situation mu st fi rs t be tau ght-
in to th e tire pressure monitoring sy st em.
In most cases, th e tire pressure monitoring sys‐
te m will au to matically update th e new re fe re nce va lues af te r yo u ha ve ch anged th e tire pressure.
Yo u can, ho we ve r, also update th e re fe re nce va l‐
ues by re st arting th e tire pressure monitoring
sy st em manually ( →
page 420).
Sy st em limitations
The sy st em may be impaired or may not function
in th e fo llowing situations: R
If th e tire pressure is set incor re ctly.R
If th ere is a sudden pressure loss caused, fo r
ex ample by a fo re ign object penetrating th e
tire. R
If th ere is a malfunction caused by ano th er
ra dio signal source.
Make sure to obser ve th e fo llowing fur th er re la‐
te d subjec t: R
No te s on tire pressure ( →
page 41 4)
Checking th e tire pressure with th e tire pres‐
sure moni to ri ng sy st em
Requ irement: R
The ignition is switched on. On-board computer:

ing condition ( →
page 41 6). Obse rv e th e
no te s on tire te mp erature ( →
page 41 4).