2018 MERCEDES-BENZ S CLASS ignition

Re st ra int sy st em functionality
When th e ignition is switched on, a sy st em self-
te st is per fo rm ed, during which th e u
re st ra int sy st em wa rn ing lamp lights up. It goes
out no later th an a fe w seconds af te r th e ve hicle
is st ar te d. The components of th e re st ra int sys‐
te m are th en functional.
Malfunctioning re st ra int sy st em
A malfunction has occur re d in th e re st ra int sys‐
te m if: R
The u re st ra int sy st em wa rn ing lamp
does not light up when th e ignition is
switched on. R
The u re st ra int sy st em wa rn ing lamp
lights up continuously or re peatedly during a
journe y. q
WA RNING Risk of inju ry or fa ta l injury
due to a malfunction in th e re st ra int sys‐
te m
If th e re st ra int sy st em is malfunctioning,
re st ra int sy st em components may be trig‐
ge re d unintentionally or might not be trig‐
ge re d at all in th e eve nt of an accident. This
may af fe ct th e Emer ge ncy Te nsioning Device
or airbag, fo r ex ample.

PA SSENGER AIR BA G indicator lamp
Sy st em self- te st
When th e ignition is switched on, a sy st em self-
te st is per fo rm ed during which th e two
PA SSENGER AIR BA G ON and OFF indicator
lamps light up simultaneousl y. The st atus of th e front passenger air bag is dis‐
pla ye d af te r th e sy st em self-tes t:R
PA SSENGER AIR BA G ON lights up fo r
60 seconds, subsequently bo th PA SSENGER
AIR BA G ON and OFF indicator lamps are off:
th e front passenger air bag is able to deploy
in th e eve nt of an accident. R
PA SSENGER AIR BA G OFF lights up continu‐
ously: th e front passenger air bag is deactiva‐
te d. It will th en not be deplo ye d in th e eve nt
of an accident.
If th e PA SSENGER AIR BA G ON indicator lamp is
off, on ly th e PA SSENGER AIR BA G OFF indicator
lamp sho ws th e st atus of th e front passenger air
bag. The PA SSENGER AIR BA G OFF indicator
lamp may be lit continuously or be off.
If th e PA SSENGER AIR BA G OFF indicator lamp
and th e u re st ra int sy st em wa rn ing lamp
light up simultaneousl y, th e front passenger seat
may not be used. Also in th is case, do not ins ta ll
a ch ild re st ra int sy st em on th e front passenger
seat. Ha ve th e automatic front passenger air bag
shutoff ch ec ke d and re paired immediately at a
qu alified specialist wo rk shop. St atus display
If th e front passenger seat is occupied, ensure,
bo th before and durin g th e
journe y, th at th e st a‐
tus of th e front passenger air bag is cor re ct fo r
th e pr eva iling situation.
Af te r in st alling a re ar wa rd -facing ch ild
re st ra int sy st em on th e front passenger
seat: PA SSENGER AIR BA G OFF must be lit con‐
tinuousl y.
q
WA RNING Risk of inju ry or death from
using a re ar wa rd -facing ch ild re st ra int
sy st em when th e front passenger air bag
is enabled
If yo u secure a ch ild in a re ar wa rd -facing
ch ild re st ra int sy st em on th e front passenger
seat and th e PA SSENGER AIR BA G OFF indi‐
cator lamp is off, th e front passenger air bag
can deploy in th e ev ent of an accident.
The ch ild could be st ru ck by th e air bag.
Alw ay s ensure th at th e front passenger air
bag is disabled. The PA SSENGER AIR BA G
OFF indicator lamp must be lit. Occupant saf et y 43

Anti-theft pr ot ection
Fu nction of th e immobilizer
The immobilizer pr eve nts yo ur ve hicle from being
st ar te d without th e cor re ct SmartK ey .
The immobilizer is automatically activated when
th e ignition is switched off and deactivated when
th e ignition is switched on.
When leaving th e ve hicle, alw ay s ta ke th e Smart‐
Ke y wit h yo u and lock th e ve hicle. An yo ne can
st art th e engine if a va lid SmartK ey has been left
inside th e ve hicle.

Ve hicles with individual re ar seats
Yo u can ch ar ge a USB device, e.g. a mobile
phone, at USB ports 1 using a suitable ch arg‐
ing cable. The devices can be ch ar ge d with 5 V
(2.1 A) and when th e ignition is switched on. Re frigerator box
Using th e re frigerator box
q
WA RNING Risk of fi re due to a co ve re d
ve nt grille on th e re frigerator box
If yo u co ve r th e ve nt grille fo r th e re frigerator
box, it may ov erheat.

The ex te ri or lighting (e xc ept parking and st and‐
ing lamps) swit ch es off automatically when th e
driver's door is opened. R
Obser ve th e no te s on sur ro und lighting
( →
page 14 7).
Au to matic driving lights
The pa rk ing lights, low beam and daytime ru n‐
ning la mp s are switched on automatically
depending on th e ignition st atus, whe th er th e
engine is ru nning and on th e ambient light.
q
WA RNING Risk of accident when th e low
beam is switched off in poor visibility
When th e light switch is set to X , th e low
beam may not be switched on automatically
if th ere is fo g, snow or ot her causes of poor
visibility such as spr ay .

Drivin g
Note s on Mercedes-AMG ve hicles
Obser ve th e no te s on th e fo llowing to pics in th e
Supplement. Otherwise, yo u may not re cognize
dangers. R
AMG Pe rf ormance ex haust sy st emR
AMG high-per fo rm ance brake sy st em and
AMG ceramic high-per fo rm ance composite
brake sy st emR
AMG adaptive sport suspension sy st em
Switching on th e po we r supp ly or ignition
using th e st art/s to p button
q
WA RNING Risk of accident and inju ry
due to ch ildren left unat te nded in th e
ve hicle
If ch ildren are left unat te nded in th e ve hicle,
th ey could: R
Open doo rs , th ereby endangering ot her
persons or ro ad users R
Get out of th e ve hicle and be hit by
oncoming traf fi c R
Operate ve hicle equipment
In addition, th e ch ildren could also set th e
ve hicle in motion, fo r ex ample, by :R
Re leasing th e parking brake R
Shifting th e transmission out of park
position ] R
St arting th e engine.

Au to matic syn chro nization
Each time th e ignition is switched off or on, th e
individual user profiles are synchronized on th e
multimedia sy st em and on th e ser ve r. This
ensures th at th e latest user profiles are alw ay s
av ailable.

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: