2011 MERCEDES-BENZ M-Class wiring

Vehicle equipment
i This manual describes all the standard
and optional equipment of your vehicle
which was available at the time of
purchase. Country-specific differences are
possible. Bear in mind that your vehicle
may not feature all functions described
here. This also refers to safety-related
systems and functions.
Occupant safety
Overview of occupant safety
In this section you will learn the most
important facts about the restraint system
components of the vehicle.
The restraint systems are:
R Seat belts
R Child restraint systems
R "LATCH" type child seat mountings
Additional protection is provided by:
R SRS (Supplemental Restraint System)
R NECK-PRO head restraints
R PRE-SAFE ®
R Air bag system components with:
- PASSENGER air bag OFF indicator lamp
- USA only: front-passenger seat with
Occupant Classification System (OCS)
- Canada only: front-passenger seat with
BabySmart™ air bag deactivation system
The protective functions of the systems work
in conjunction with each other. The systems
are, however, autonomous.
GWarning!
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/
belt buckle tensioners, for example, could
deploy inadvertently or fail to deploy.
Therefore, never modify the restraint
systems. Do not tamper with electronic
components or their software.
i More information on the subject of
children in the vehicle and child restraint
systems can be found under the "Children
in the vehicle" chapter ( Y page 58).
SRS (Supplemental Restraint System)
Introduction
SRS reduces the risk of occupants coming
into contact with the vehicle's interior in the
event of an accident. It can also reduce the
effect of the forces to which occupants are
subjected during an accident.
SRS consists of:
R + SRS warning lamp
R air bags
R air bag control unit (with crash sensors)
R ETDs/belt buckle tensioners
R belt force limiters
SRS warning lamps
SRS functions are checked regularly when
you switch on the ignition and when the
engine is running. Therefore, malfunctions
can be detected in good time.
The + SRS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out no later than a few seconds
after the engine is started.
The SRS components are in operational
readiness when the + indicator lamp goes
out while the engine is running.
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GWarning
The SRS self-check has detected a
malfunction if the + SRS warning lamp:
R does not illuminate
R goes out approximately 4 seconds after the
engine is started
R illuminates after the engine is started or
illuminates during the journey
For your safety, Mercedes-Benz recommends
that you have the system checked as soon as
possible at an authorized Mercedes-Benz
Center. Otherwise the SRS may not be
activated when it is needed in an accident,
which could result in serious or fatal injury.
The SRS might also deploy unexpectedly and
unnecessarily which could also result in
injury.
In addition, improper work on the SRS creates
a risk of rendering the SRS inoperative or
causing unintended air bag deployment. Work
on the SRS must therefore only be performed
by qualified technicians. Contact an
authorized Mercedes-Benz Center.
Contact an authorized Mercedes-Benz Center
if it is necessary to modify an air bag system
to accommodate a person with disabilities.
USA only: Call our Customer Assistance
Center at 1-800-FOR-MERCedes
(1-800-367-6372) for details.
Safety guidelines for seat belts,
Emergency Tensioning Devices (ETDs)
and air bags
GWarning
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. California residents, 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. PRE-
SAFE ®
has electrically operated reversible
belt tensioners in addition to the
pyrotechnic ETDs.
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 No modifications of any kind may be made
to any components or wiring of the SRS.
R Do not change or remove any component
or part of the SRS.
R Do not install additional trim material, seat
covers, badges, etc. to the:
- padded steering wheel boss
- front-passenger air bag cover
- outer side of front seat bolsters
- outer side of the seat bolsters of the rear
bench seat backrest
- roof lining trim
R Do not install additional electrical/
electronic equipment on or near SRS
components and wiring.
R Keep area between air bags and occupants
free of objects (e.g. packages, purses,
umbrellas, etc.).
R Do not hang items such as coat hangers
from the coat hooks or handles over the
door. These items may be thrown around in
the vehicle and cause head and other
injuries when the window curtain air bag is
deployed.
R Air bag system components will be hot after
an air bag has inflated. Do not touch them.Occupant safety37SafetyBA 164.1 USA, CA Edition B 2011; 1; 2, en-USd2mskotVersion: 3.0.3.52010-04-21T17:25:06+02:00 - Seite 37Z

Message in the multifunction display
Diff. Lock System Overheated -
Wait briefly.
The differential lock system has overheated
and briefly disengaged.XContinue driving.
The differential locks cool off and are soon
available once again.
Towing a trailer
Notes on towing a trailer
Important safety instructions
GWarning!
Failure to use proper equipment and driving
technique can result in a loss of vehicle
control when towing a trailer.
Improper towing or failure to follow the
instructions in this manual can result in
vehicle damage and/or serious personal
injury. Follow the guidelines below carefully
to assure safe trailer operation.
Contact an authorized Mercedes-Benz Center
should you require an explanation of
information contained in this manual.
General information
R Only install an approved trailer coupling on
your vehicle.
Further information on availability and on
installation is available from any authorized
Mercedes-Benz Center.
R The bumpers of your vehicle are not
suitable for installing detachable trailer
couplings.
R Do not install hired trailer couplings or
other detachable trailer couplings on the
bumpers of your vehicle.
R To reduce the risk of damage to the ball
coupling, remove it from the ball coupling
recess when not in use.
Coupling up a trailerGWarning!
Vehicles with air suspension program: While
you are coupling or decoupling a trailer, make
sure nobody locks or unlocks the vehicle and/
or opens or closes doors or the tailgate.
The vehicle’s level could change and you
could endanger yourself and/or others as a
result.
Make sure that you do not operate the ADS
switch or the vehicle level control system
when coupling/decoupling the trailer.
Observe the maximum permissible trailer
dimensions (width and length).
Most federal states and all Canadian
provinces require by law:
R safety chains between the towing vehicle
and the trailer. The chains should be cross-
wound under the trailer drawbar. They must
be fastened to the vehicle's trailer
coupling, not to the bumper or the axle.
Allow for enough play in the chains to
facilitate turning tight corners.
R a separate brake system for certain types
of trailer.
R a safety switch for braked trailers. Check
the specific legal requirements applicable
to your federal state.
If the trailer detaches from the towing
vehicle, the safety switch applies the
trailer's brakes.
! Do not connect the trailer's brake system
(if featured) to the hydraulic brake system
of the towing vehicle, as the latter is
equipped with an anti-lock brake system.
Doing so will result in a loss of function of
the brake systems of both the vehicle and
the trailer.
i The vehicle's wiring harness features a
line to the brake indicator lamp.
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