2012 MERCEDES-BENZ A-CLASS HATCHBACK wiring

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 could effect their
function and/or the operation of other net-
worked components. This could in particular
also be the case for systems relevant to
safety. They might not function properly any
more and/or jeopardise the operational
safety of the vehicle. There is an increased
risk of an accident and injury.
Do not attempt to modify the wiring as well as
electronic components or their software.
Always have work on electrical and electronic components carried out at a qualified special-
ist workshop.
There is a risk of damage to the vehicle if:
R the vehicle becomes stuck, e.g. on a high
kerb or an unpaved road
R you drive too fast over an obstacle, e.g. a
kerb 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 undercar- riage, chassis parts, wheels or tyres could be
damaged without the damage being visible.
Components damaged in this way can unex-
pectedly fail or, in the case of an accident, no
longer withstand the strain they are designed
to.
If the underbody panelling is damaged, com-
bustible materials such as leaves, grass or
twigs can gather between the underbody and the underbody panelling. 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 imme-
diately at a qualified specialist workshop. If on
continuing your journey you notice that driv-
ing 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
Wireless vehicle components The following information applies to all com-
ponents of the vehicle and the COMAND sys-
tem which receive and/or transmit radio
waves:
The components of this vehicle which receive
and/or transmit radio waves are compliant
with the basic requirements and other rele-
vant provisions of Directive 1999/5/EC. You can obtain further information from any
Mercedes-Benz Service Centre.
Electromagnetic compatibility The electromagnetic compatibility of the vehi-
cle components has been checked and certi-
fied according to the currently valid version of Directive 72/245/EE Cor the equivalent ECE
Regulation ECE-R 10. Diagnostics connection
The diagnostics connection is only intended
for the connection of diagnostic equipment at
a qualified specialist workshop. G
WARNING
If you connect equipment to a diagnostics
connection in the vehicle, it can affect the
operation of the vehicle systems. This may
affect the operating safety of the vehicle.
There is a risk of an accident.
Do not connect any equipment to a diagnos-
tics connection in the vehicle. Introduction
23 Z

Useful information
i This Owner's Manual describes all mod-
els, series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos- sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: (Y page 24). Occupant safety
Important safety notes
G
WARNING
If service work is not carried out correctly, the operating safety of your vehicle may be affec-
ted. This could cause you to lose control of
your vehicle and cause an accident. More-
over, the safety systems may no longer be
able to protect you or others as they are
designed to do.
Always have service work carried out at a
qualified specialist workshop. G
WARNING
Modifications to or work performed incor-
rectly on the following parts can result in the
restraint systems not functioning as intended:
R the restraint system, consisting of seat
belts and their anchorage points, belt ten-
sioners, belt force limiters and airbags
R the wiring
R networked electronic systems
Airbags and belt tensioners could fail to
deploy or be triggered in an accident despite
the deceleration force being sufficient to trig-
ger the systems, or could be triggered unin-
tentionally. For this reason, never make any
modifications to the restraint systems.
Therefore, you must not tamper with elec-
tronic components or their software. The seat belts, together with SRS (Supple-
mental Restraint System), are complemen-
tary, co-ordinated restraint systems
(Y
page 41). They reduce the risk of injury in
specific, pre-defined types of accident situa-
tions and thereby increase occupant safety.
However, seat belts and airbags generally do
not protect against objects penetrating the
vehicle from the outside.
To ensure that the restraint systems can
deliver their full potential protection, make
sure that:
R the seat and head restraint are adjusted
properly (Y page 92)
R the seat belt has been fastened properly
(Y page 46)
R the airbags can inflate unrestricted if
deployed (Y page 42)
R the steering wheel is adjusted properly
(Y page 98)
R the restraint systems have not been modi-
fied
An airbag increases the protection of vehicle
occupants wearing a seat belt. However, air-
bags are only an additional restraint system
which complements, but does not replace,
the seat belt. All vehicle occupants must wear their seat belt correctly at all times, even if thevehicle is equipped with airbags. The airbags
are not deployed in all types of accidents. For example, if the protective capacity of cor-
rectly fastened seat belts is not increased by
deploying the airbags, the airbags will not
deploy.
Airbag deployment only provides increased
protection if the seat belt is worn correctly.
The seat belt helps, firstly, to keep the vehicle
occupant in the best position in relation to the airbag. Secondly, in a head-on collision, for
example, the seat belt prevents the vehicle
occupant from being propelled towards the
point of impact. 40
Occupant safetySafety

Approved aerial positions
:
Front roof area
; Rear roof area
= Rear wing
i On vehicles with panorama sliding sun-
roof, fitting an aerial to the front roof area is not permitted.
On the rear wing, it is recommended that
you position the aerial on the side of the
vehicle closest to the centre of the road.
Use Technical Specification ISO/TS 21609
(Road Vehicles – "EMC guidelines for fitting
aftermarket radio frequency transmitting
equipment") when retrofitting RF (radio fre-
quency) transmitters. Comply with the legal
requirements for add-on parts.
If your vehicle has fittings for two-way radio
equipment, use the power supply or aerial
connections intended for use with the basic
wiring. Be sure to observe the manufacturer's additional instructions when installing.
Deviations with respect to wavebands, maxi-
mum transmission outputs or aerial positions must be approved by Mercedes-Benz. The maximum transmission output (PEAK) at
the base of the aerial must not exceed the
following values: Waveband Maximum
transmission output Short wave
3 - 54 MHz 100 W
4 m waveband
68 - 87.5 MHz 30 W
2 m waveband
144 - 174 MHz 50 W
Trunked radio/Tetra
380 - 460 MHz 35 W
70 cm waveband
400 - 460 MHz 35 W
GSM/DCS/PCS
850/900/1800/1900 10 W
UMTS/LTE 10 W
The following can be used in the vehicle with-
out restrictions:
R RF transmitters with a maximum transmis-
sion output of up to 100 mW
R mobile phones (GSM/DCS/PCS/UMTS/
LTE)
There are no restrictions when positioning the aerial on the outside of the vehicle for the fol-
lowing wavebands:
R Trunked radio/Tetra
R 70 cm waveband
R GSM/DCS/PCS
R UMTS/LTE Vehicle electronics
337Technical data Z