2014 AUDI S8 wiring

160 Airbag sys te m
- Always make su re the forward-facing
seat has been des igned and certified by
its manufacturer for use on a front seat
with a passenger front a nd side airbag .
- Never put the forward- facing child re­
straint up aga inst or very near the instru­
ment panel.
- Always move the passenger seat into its
rearmost position in the seat's fore and
aft adjustment range, as far away from
the a irbag as poss ible, before insta lli ng
the fo rward-facing chi ld restraint. The
b ackres t must be adjusted to an upr igh t
posit ion.
- Make su re that the
PASSENGER AIR BAG
OFF
light co m es on and s tays on all the
t ime whenever the ignition is switched
on.
Advanced Airbag System components
The front passenger seat in your vehicle has a lot of very important parts of the Advanced
Airbag System in it. These parts include the
weight-sens ing mat, sensors, wiring, brack­
ets, and more . The function of the system in
the front passenger seat is checked by the
e lectronic control u nit when the ignit ion is on.
The control unit mo nitors the Advanced Air­
bag Sys tem and turns the airbag indicator
light on when a ma lfunction in the system
components is detected . The function of the
ai rbag ind icator light is described in greater
detai l below. Because the front passenger
seat contains important parts of the Ad­
vanced A irbag System, you must take care to
prevent it from be ing damaged . Damage to
the seat may prevent the Advanced A irbag for
the front passenger seat from doing its job in
a cra sh .
The front Advanced Airbag System
consists of the following:
- Crash senso rs in the front of the veh icle that
measu re ve hicle ac celera tion/de ce le ra ti on
to provide information to the Advanced Air­ bag System abo ut the severity of the crash . -
An elect ronic contro l unit, with integrated
crash sensors for front and side impacts .
The control un it "decides" whether to fi re
the front a irbags based on the informat ion
received from the crash sensors. The contro l
un it also "decides" whether the safety belt
prete nsioners shou ld be act ivated .
- An Advanced A irbag w ith gas generator and
cont ro l valve for the driver ins ide the steer ­
ing wheel hub .
- An Advanced A irbag w ith gas generator and
cont ro l valve inside the inst rument panel for
the front passenger .
- A we ight-sensing mat under the up ho lstery
padding of the front passenge r seat cushion
that measures the total weight o n the seat.
The info rma tion reg iste red is sent continu­
ously to the elec troni c control un it to regu­
la te deployment o f the front Advanced Air ­
bag on the passenger side .
- An airbag monitor ing sys tem and indicator
light in t he instr ument cluster ¢
page 164.
-A sensor in each front se at regis ters the dis ­
t ance between the respec tive seat and the
steering whee l o r instrument panel. The in­
formation registered is sent continuo usly to
the electron ic contro l unit to regulate de­
ployment of the front Adv a need A irbags .
- The
PASSENGER AIR BAG OFF light comes
on and stays on in the center of the instr u­
ment panel ¢
page 164, fig. 168 and tells
you whe n the front Advanced Airbag on the
passe nger side has been turned off .
- A sensor below the safety be lt latch for the
front seat passe nger to measure the tension
on t he safety be lt . The tension on the safety
be lt and the weight registered by t he
weight-sens ing mat he lp the control uni t
"de cide" whe ther the front airbag fo r the
front passenge r seat should be turned off or
not ~
page 155 , Child restraints on the
front seat -some important things to
know.
- A sensor in the safety belt latch fo r th e d riv ­
er and for the front seat passenger that
senses whether that safety belt is latched or not and transmits this information to the
electronic control un it .

164 Airbag system
Monitoring the
Advanced Airbag System
Cl! (USA models)/!f (Canada models)
Airbag monitoring indicator light
Two separate indicators monitor the function
of the Advanced Airbag System: the airbag
monitoring indicator light and the
PASSEN­
GER AIR BAG OFF
light.
The Advanced Airbag System (including the
electronic control unit, sensor circuits and sys­
tem wiring) is monitored continuously to
make sure that it is functioning properly
whenever the ignition is on. Each time you
switch on the ignition, the airbag monitoring
indicator light
I (USA mode ls)/ fll (Canada
models) will come on for a few seconds (self
d iagnost ics).
The system must be inspected when the
indicator light
I (USA models)/E,I
(Canada models):
-does not come on when the ignition is
switched on,
- does not go out a few seconds after you have switched on the ignition, or
- comes on while driving.
If an airbag system malfunct ion is dete cted,
the indicator light will first start flashing to
catch the driver's attention and then stay on
continuously to serve as a constant reminder
to have the system inspected immediately.
If a malfunction occurs that turns the front
airbag on the passenger side
off, the PASSEN­
GER AIR BAG OFF
light will come on and stay
on whenever the ignition is on.
A WARNING
An airbag system that is not functioning
properly cannot provide supplemental pro­
tection in a frontal crash.
- If the airbag indicator light
c::> page 18
comes when the vehicle is be ing used,
have the system inspected immediate ly
by your authorized Audi dealer. It is pos- sible
that the airbag will inflate when it
is not supposed to, or will not inflate
when it should.
PASSENGER AIR BAG OFF light
Fig. 168 Sect io n from the instrument pane l: PASSEN­
GER AIR BAG O FF lig ht
The PASSENGER AIR BAG OFF light is located
in the center of the instrument panel
c::>fig . 168 .
The PASSENGER AIR BAG OFF light will come
on and stay on to tell you when the front Ad­
vanced Airbag on the passenger s ide has been
turned
off by the electron ic control unit. Each
t ime you switch on the ign it ion, the
PASSEN­
GER AIR BAG OFF
light will flash for a few
seconds and:
- will stay on if the front passenger seat is not
occupied,
- will stay on if there is a small ch ild or child
restraint on the front passenger seat,
- w ill go out if the front passenger seat is oc ­
cupied by an adult as registered by the
weight-sensing mat.
The
PASSENGER AIR BAG OFF light must
come on and stay on
if the ignition is on and
- a car bed has been installed on the front seat, or
- a rearward-facing child restraint has been
installed on the front passenger seat, or
- a forward-facing child restraint has been in-
stalled on the front passenger seat, or
liJI,

212 Trailertowing
Trailer towing Driving with a trailer
General information
Your Audi was designed primarily for passen­
ger transportation .
If you plan to tow a trai ler, please remember
that the additional load will affect durability,
economy and performance .
Trailer towing not only places more stress on the vehicle, it also calls for more concentra­
tion from the driver.
For this reason, always follow the operating
and driving instructions provided and use
common sense.
(D Note
If you are going to tow a trai ler, you must
activate the trailer operation mode
i::> page 212, Operating instructions .
Technical requirements
Trailer hitch
Use a weight-carrying hitch conforming to the
gross trailer weight. The hitch must be suita­ ble for your vehicle and trailer and must be
mounted securely on the veh icle 's chassis at a
technically sound location . Use only a trailer
hitch with a removable ball mount. A lways
check with the trai le r hitch manufacturer to
make sure that you are using the cor rect
hitch.
Do not use a bumper hitch.
The hitch must be installed in such a way that
it does not interfere with the impact-absorb­
ing bumper system. No modifications should
be made to the vehicle exhaust and brake sys­
tems. From time to time, check that all hitch
mounting bo lts remain securely fastened.
When you are not towing a trailer, remove the
trailer hitch ball mount. This prevents the
h itch from causing damage should your veh i­
cle be struck from behind~ &.
Trailer brakes
If your trailer is equipped with a brak ing sys­
tem, check to be sure that it conforms to all
regulations.
T he trailer hydraulic brake system must not be
direc tly connected to the vehicle's hydraulic
brake system .
Safety chains
Always use safety chains between your veh icle
and the tra iler.
Trailer lights
Trailer lights must meet all regulations. Be
sure to check with your Audi dealer for correct
wiring, switches and relays.
Mirrors
If you are unable to see the traffic behind you
using the regular outside mirrors, then you
must install extended mirrors. It is important
that you
always have clear v is ion to the rear .
A WARNING ,~ -
After removing the trailer hitch, do not
store it in your vehicl e. In case of sudden
braking, the hitch could fly forward and in­
jure you or your passengers.
Operating instructions
Fig. 189 MMI display : tow ing mode on
Maximum traile r weight
A trai ler for your vehicle is limited to a typical
class 1 or class 2 trailer. .,.