2012 MERCEDES-BENZ B-CLASS wiring

Operating safety
Important safety notes
G
WARNING
If you do not have the prescribed service/
maintenance work or any required repairs
carried out, this
can result in malfunctions or
system failures. There is a risk of an accident.
Always have the prescribed service/
maintenance work as well as any required
repairs carried out at a qualified specialist
workshop. G
WARNING
If you switch off the ignition while driving,
safety-relevant functions are only available
with limitations, or

not at all. This could affect,
for example, the power steering and the brake
boosting effect. You will require considerably
more effort to steer and brake. There is a risk
of an accident.
Do not switch off the ignition while driving. G
WARNING
Modifications to electronic components, their
software as well as wiring can impair their
function and/or the function of other
networked components. In particular,
systems relevant to safety could also be
affected. As a result, these may no longer
function as intended and/or jeopardize the
operating safety of the vehicle. There is an
increased risk of an accident and injury.
Never tamper with the wiring as well as
electronic components or

their software. You
should have all work to electrical and
electronic equipment carried out at a qualified
specialist workshop.
There is a risk of damage to the vehicle if:
R the vehicle becomes stuck, e.g. on a high
curb or an unpaved road
R you drive too fast over an obstacle, e.g. a
curb or a hole in the road
R a heavy object strikes the undercarriage or
parts of the chassis. In situations like this, the body, the
undercarriage, chassis parts, wheels or tires
could be
damaged

without the damage being
visible. Components damaged in this way can
unexpectedly fail or, in the case of an
accident, no longer withstand the strain they
are designed to.
If the underbody paneling is damaged,
combustible materials such as leaves, grass
or twigs can gather between the underbody
and the underbody paneling. If these
materials come in contact with hot parts of
the exhaust system for an extended period,
they can catch fire.
Have the vehicle checked and repaired
immediately at a qualified specialist
workshop. If on continuing your journey you
notice that driving safety is impaired, pull over
and stop the vehicle immediately, paying
attention to road and traffic conditions. In
such cases, visit a qualified specialist
workshop. Declarations of conformity
Vehicle components which receive
and/or transmit radio waves USA: "The wireless devices of this vehicle
comply with Part 15 of the FCC Rules.
Operation is subject to the following two
conditions: 1) These devices may not cause
harmful interference, and 2) These devices
must accept any interference received,
including interference that may cause
undesired operation. Changes or
modifications not expressly approved by the
party responsible for compliance could void
the user’s authority to operate the
equipment."
Canada:
"The wireless

devices of this vehicle
comply with Industry Canada license-exempt
RSS standard(s). Operation is subject to the
following two conditions: (1) These devices
may not cause interference, and (2) These
devices must accept any interference, Introduction
23 Z
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Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note
that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: ( Y page 24).Panic alarm
X
To activate: press ! button : for at
least one second.
An alarm sounds and the exterior lighting
flashes.
X To deactivate: press ! button :
again.
or
X Insert the SmartKey into the ignition lock. Occupant safety
Important safety notes
G
WARNING
Modifications to or work improperly
conducted on restraint system components
or their wiring, as well as tampering with interconnected electronic systems, can lead
to the
restraint
systems no longer functioning
as intended.
Air bags or Emergency Tensioning Devices
(ETDs), for example, could deploy
inadvertently or fail to deploy in accidents
although the deceleration threshold for air
bag deployment is exceeded. Therefore,
never modify the restraint systems. Do not
tamper with electronic components or their
software.
In this section, you will learn the most
important facts about the restraint system
components of the vehicle.
The restraint system consists of:
R Seat belts
R Child restraint systems
R LATCH-type (ISOFIX) child seat securing
system
Additional protection is provided by:
R SRS (Supplemental Restraint System)
R Air bag system components with the
PASSENGER AIRBAG OFF indicator lamp
The different air bag systems work
independently of each other. The protective
functions of the system work in conjunction
with each other. Not all air bags are always
deployed in an accident.
i For information on infants and children
traveling with you in the vehicle restraint
systems for infants and children, see
"Children in the vehicle" ( Y page 50). SRS (Supplemental Restraint System)
Introduction Supplemental Restraint System (SRS) with:
R
The 6 SRS warning lamp
R Air bags
R Air bag control unit (with crash sensors)38
Occupant safety
Safety
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R
the deformation characteristics of the
vehicle
R the characteristics of
the object with which
the vehicle has collided
Factors that can only be seen and measured
after a collision has occurred do not play a
decisive role in the deployment of an air bag,
nor do they provide an indication of air bag
deployment.
The vehicle may be deformed significantly,
e.g. the hood or the fender, without an air bag
being deployed. This is the case if only parts
which are relatively easily deformed are
affected and the rate of deceleration is not
high. Conversely, air bags may be deployed
even though the vehicle suffers only minor
deformation. This is the case if, for example,
very rigid vehicle parts such as longitudinal
body members are hit, and sufficient
deceleration occurs as a result.
i The front Emergency Tensioning Devices
can only be triggered if the seat belt
tongues on the front seats are correctly
engaged in the seat belt buckles.
i Not all air bags are deployed in an
accident. The different air bag systems
work independently of each other.
How the air bag system works is
determined by predicting the severity of
the accident, especially vehicle
deceleration or acceleration, and the type
of accident:
R head-on collision
R side impact
R rollover
Safety guidelines for seat belts,
Emergency Tensioning Devices (ETDs)
and air bags G
WARNING
R Damaged seat belts

or seat belts that have
been subjected to stress in an accident
must be replaced. Their anchoring points
must also be checked. Only use seat belts installed or supplied by an authorized
Mercedes-Benz Center.
R Air bags and pyrotechnic Emergency
Tensioning Devices (ETDs) contain
perchlorate material, which may require
special handling and regard for the
environment. Check your

national disposal
guidelines. In California, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm.
R Air bags and ETDs are designed to function
on a one-time-only basis. An air bag or ETD
that has deployed must be replaced.
R Do not pass seat belts over sharp edges.
They could tear.
R Do not make any modification that could
change the effectiveness of the seat belts.
R Do not bleach or dye seat belts, as this may
severely weaken them. In a crash, they may
not be able to provide adequate protection.
R Do not make any modifications to the SRS
wiring or components.
R Do not modify or remove any components
or parts of the SRS.
R Do not install additional trim material, seat
covers, badges, etc. to the:
-padded steering wheel boss
- knee bag covers
- front-passenger air bag cover
- outer side of front seat bolsters
- outer seat bolsters of the rear bench seat
backrest
- roof frame trim
R Do not install additional electrical/
electronic equipment on or near SRS
components and wiring.
R Keep the area between the air bags and
occupants free of objects (e.g. packages,
handbags, umbrellas etc.).
R Do not hang any objects such as coat
hangers on the coat hooks or the grab
handle above the door. These items may be
thrown around in the vehicle and cause40
Occupant safety
Safety
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