bus AUDI A8 2003 D3 / 2.G Technical Features Manual

Downloaded from www.Manualslib.com manuals search engine Complete vehicle information
The design and operation of the Audi A8 ´03 are described in the following Self Study
Programmes:
Other helpful information on the
Audi A8 ´03 can be found on the adjacent
CD ROMs.
Electrical system CAN data bus 2
SSP 283 – 6-speed automatic gearbox 09E in the Audi A8 '03 - Part 1
SSP 284 – 6-speed automatic gearbox 09E in the Audi A8 '03 - Part 2
SSP 285 – Running gear in the Audi A8 '03
SSP 286 – New data bus systems - LIN, MOST, Bluetooth
TM
SSP 287 – Audi A8 '03 - Electrical components
SSP 288 – Audi A8 '03 - Distributed functions
SSP 289 – Adaptive cruise control in the Audi A8 '03
SSP 292 – Adaptive air suspension in the Audi A8 '03
SSP 293 – Audi A8 '03 - Infotainment

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Attention
NoteNew
Contents
Page
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Passenger Protection
System layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Safety systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Engine, Mechanics
Technical data of V8 4.2 l 5V engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Technical data of V8 3.7 l 5V engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
System layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Electrohydraulic torque reaction support . . . . . . . . . . . . . . . . . . . . . . . . . 32
Exhaust system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Fuel tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Automatically controlled starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Gearbox . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Running Gear
Front axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Rear axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
4-level air suspension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
System layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Electric parking brake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Adaptive cruise control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Electrical System
Bus topology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Convenience and security electronics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Lighting system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Heating/Air Conditioner
Design and operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Operating principle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Blower unit/air routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
System layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Block diagram for front air conditioner . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Block diagram for rear air conditioner . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
The Self Study Programme contains information on design
features and functions.
The Self Study Programme is not intended as a Workshop
Manual. Values given are only intended to help explain the
subject matter and relate to the software version applicable at
the time of SSP compilation.
Use should always be made of the latest technical publications
when performing maintenance and repair work.

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The wide range of sensors permits detection
not only of head-on collision and side impact,
but also of rear-end collisions. Use is made in the Audi A8 ´03 of the 8.4E+
airbag system with the aim of attaining greater
occupant safety whilst reducing the impact.
This was achieved, for example, by way of two-
stage front airbag triggering, active front head
restraints and a battery cut-off element.
K75 Airbag warning lamp
K145 Airbag disabled warning lamp,
front passenger side
N95 Driver side airbag igniter
N131 Airbag igniter 1, front passenger side
N153 Belt tensioner igniter 1, driver side
N154 Belt tensioner igniter 2,
front passenger side
N196 Rear belt tensioner igniter,
driver side
N197 Rear belt tensioner igniter,
front passenger side
N198 Rear belt tensioner igniter,
centre
N199 Side airbag igniter, driver side
N200 Side airbag igniter,
front passenger side
N201 Rear side airbag igniter,
driver side
N202 Rear side airbag igniter,
front passenger side
N251 Curtain airbag igniter, driver side
N252 Curtain airbag igniter,
front passenger side
T16 16-pin connector
(diagnostic connection) Key
E24 Driver side belt switch
E25 Front passenger side belt switch
E224 Airbag disabling key switch,
front passenger side
G85 Steering angle sender
G179 Side airbag crash sensor,
driver side (B-pillar)
G180 Side airbag crash sensor,
front passenger side (B-pillar)
G256 Rear side airbag crash sensor,
driver side
G257 Rear side airbag crash sensor,
front passenger side
G283 Front airbag crash sensor,
driver side
G284 Front airbag crash sensor,
front passenger side
J234 Airbag control unit
J285 Control unit with display
in dash panel insert
J393 Convenience system central
control unit
J526 Telephone/telematics control unit
J533 Data bus diagnostic interface
(gateway)
J623 Engine control unit
J655 Battery cut-off relay

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Hot-film air-mass meter G70
Engine speed sender G28
Hall sender G40 (bank 2) and
Hall sender 2 G163 (bank 1)
Lambda probe G39
(bank 1)
Lambda probe II G108
(bank 2)
Lambda probe after catalyst G130
(bank 1)
Lambda probe II after catalyst G131
(bank 2)
Throttle valve control
part J338 with
Throttle valve drive G186
(electric power control)
Throttle valve drive angle sender 1 G187
Throttle valve drive angle sender 2 G188
Coolant temperature sender G62
Knock sensor I G61 (bank 1) and
Knock sensor II G66 (bank 2)
Additional signals:
– Air conditioner requirement
– Cruise control switch
– Term. 50, stage 1
– Automatic gearbox selector lever positionEngine control unit J623
Steering
angle sender G85
ESP
control unit J104
Dash panel
insert CANAutomatic
gearbox
control unit J217
Airbag
control unit J234Intake manifold changeover valve
N156 and
Intake manifold changeover valve 2
N261
Left electrohydraulic engine mounting
solenoid valve N144 and
Right electrohydraulic engine mounting
solenoid valve N145
Torque rod valve N382
Lambda probe heater Z19
(bank 1) and
Lambda probe 2 heater Z28
(bank 2)
Lambda probe 1 heater
after catalyst Z29
Lambda probe 2 heater
after catalyst Z30
Additional signals:
– Starter relay term. 50, stage 2
– Tank leakage pump (USA only)
– Air conditioner compressor (out)Fuel pump relay J17
Fuel pump G6
Fuel pump II relay J49
Fuel pump G23
Injectors N30, N31, N32, N33 (bank 1)
Injectors N83, N84, N85, N86 (bank 2)
Ignition coils N (no. 1 cyl.), N128 (no. 2 cyl.),
N158 (no. 3 cyl.), N163 (no. 4 cyl.)
Ignition coils N164 (no. 5 cyl.), N189 (no. 6 cyl.),
N190 (no. 7 cyl.), N191 (no. 8 cyl.)
Activated charcoal filter system solenoid
valve 1 N80
Secondary-air pump relay J299 and
Secondary-air pump motor V101
Secondary air inlet valve N112
Throttle valve control part J338
With throttle valve drive G186
Inlet camshaft timing adjustment valve 1
N205 (bank 1)
and
N208 (bank 2) Pedal position sender/accelerator
pedal module with accelerator pedal
position sender G79 and accelerator
pedal position sender 2 G185
Brake light switch F and
Brake pedal switch F47
Clutch pedal switch F36
(manual gearbox only)
Control unit with display in dash
panel insert J285Data bus diagnostic
interface J533
Engine, Mechanics
System layout
Actuators/sensors
SSP282_091 Drive system CAN
Diagnosis CAN

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Hot-film air-mass meter G70
Engine speed sender G28
Hall sender G40 (bank 2) and
Hall sender 2 G163 (bank 1)
Lambda probe G39
(bank 1)
Lambda probe II G108
(bank 2)
Lambda probe after catalyst G130
(bank 1)
Lambda probe II after catalyst G131
(bank 2)
Throttle valve control
part J338 with
Throttle valve drive G186
(electric power control)
Throttle valve drive angle sender 1 G187
Throttle valve drive angle sender 2 G188
Coolant temperature sender G62
Knock sensor I G61 (bank 1) and
Knock sensor II G66 (bank 2)
Additional signals:
– Air conditioner requirement
– Cruise control switch
– Term. 50, stage 1
– Automatic gearbox selector lever positionEngine control unit J623
Steering
angle sender G85
ESP
control unit J104
Dash panel
insert CANAutomatic
gearbox
control unit J217
Airbag
control unit J234Intake manifold changeover valve
N156 and
Intake manifold changeover valve 2
N261
Left electrohydraulic engine mounting
solenoid valve N144 and
Right electrohydraulic engine mounting
solenoid valve N145
Torque rod valve N382
Lambda probe heater Z19
(bank 1) and
Lambda probe 2 heater Z28
(bank 2)
Lambda probe 1 heater
after catalyst Z29
Lambda probe 2 heater
after catalyst Z30
Additional signals:
– Starter relay term. 50, stage 2
– Tank leakage pump (USA only)
– Air conditioner compressor (out)Fuel pump relay J17
Fuel pump G6
Fuel pump II relay J49
Fuel pump G23
Injectors N30, N31, N32, N33 (bank 1)
Injectors N83, N84, N85, N86 (bank 2)
Ignition coils N (no. 1 cyl.), N128 (no. 2 cyl.),
N158 (no. 3 cyl.), N163 (no. 4 cyl.)
Ignition coils N164 (no. 5 cyl.), N189 (no. 6 cyl.),
N190 (no. 7 cyl.), N191 (no. 8 cyl.)
Activated charcoal filter system solenoid
valve 1 N80
Secondary-air pump relay J299 and
Secondary-air pump motor V101
Secondary air inlet valve N112
Throttle valve control part J338
With throttle valve drive G186
Inlet camshaft timing adjustment valve 1
N205 (bank 1)
and
N208 (bank 2) Pedal position sender/accelerator
pedal module with accelerator pedal
position sender G79 and accelerator
pedal position sender 2 G185
Brake light switch F and
Brake pedal switch F47
Clutch pedal switch F36
(manual gearbox only)
Control unit with display in dash
panel insert J285Data bus diagnostic
interface J533
Engine, Mechanics
System layout
Actuators/sensors
SSP282_091 Drive system CAN
Diagnosis CAN

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All axle components are new on account of
the geometric and kinematic modifications as
compared to the predecessor model, the air
suspension and the weight reductions
achieved.
Rear axle highlights
– Use of air suspension in conjunction with
electronically controlled damping
– Aluminium subframe to help
reduce weight
– Connection of anti-roll bar to trapezium
link
– Use of shorter track rod to reduce change
in toe on compression and extension of
suspension
– Use of ball studs to connect wheel bearing
housing and track rod, thus reducing
secondary spring rate
– Use of slotted bonded rubber bushes in
upper transverse link and connection
between trapezium link and subframe
Rear axle design and operation are
described in SSP 285.
Rear axle
The rear axle is a more advanced version of
the familiar Audi A8 trapezium-link axle.
Running Gear
SSP282_051

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Bus topology
Electrical System
The increasing demand for additional
functions and convenience in the vehicle calls
for the use of ever more wide ranging
electronics.
The increased use of electronics also requires
a new approach to data transfer between the
individual control units. This also applies to
the Audi A8 ´03, in which more than 70 control
units have to communicate.
Distance regulation
control unit J428
Electric park and
handbrake control
unit J540Headlight range
control unit
J431Airbag control unit
J234ABS with EDL
control unit
J104
Engine control unit
J623Adaptive
suspension control
unit J197 Engine control
unit 2 J624Automatic gearbox
control unit
J217
Anti-theft/
tilt system control
unit J529
Boot lid control unit
J605Wiper motor control
unit J400Garage door
operation control
unit J530 Multifunction
steering wheel
E221
Convenenience
system central
control unit J393On-board power
supply control unit
J519
On-board power
supply control unit 2
J520Steering column
electronics control
unit J527Steering angle
sender G85
Driver side door
control unit J386Front passenger
side door
control unit J387Rear left door
control unit J388Rear right door
control unit J389Seat adjustment
control unit
J136Front passenger
seat adjustment
control unit J521 Control unit with
display in dash panel
insert J285
Diagnostic connection T16
Dash panel insert CAN
Drive system CAN
Diagnosis CAN
Convenience CAN
Internal bus link
LIN
Adaptive cruise control
CAN

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Telephone/
telematics control
unit J526
Front information
display and operating
unit control unit J523Rear DVD changer
R162Telephone
handset
R37
Control unit for rear
left
information display
and operating
unit J648
DSP control unit
J525
Navigation system
control unit
J401
TV tuner
R78
Digital radio
R147
Radio module R Chip card reader
control unit
J676 CD changer
R41 CD ROM drive
R92 Data bus diagnostic
interface J533
Fresh-air blower
control unit
J126Heated windscreen
control unit J505Rear left footwell
heater element Z42Rear right footwell
heater element Z43Driver seat
ventilation
control unit J672Front passenger
seat ventilation
control unit J673

Parking aid control
unit J446 Entry and start
authorisation
control unit J518 Energy
management
control unit J644 Rear seat
adjustment with
memory control
unit J522 Climatronic control
unit J255
Trailer detector
control unit J345
Rear Climatronic
control and
display unit E265Tyre pressure
monitor control unit
J502
Sun roof electronics
control unit J528
Additional heater
control unit J364Driver identification
control unit J589
Auxiliary heating
radio controlled
receiver R64 Sliding sun roof
motor V1 Front passenger
side rear seat
ventilation
control unit J675 Driver side rear seat
ventilation control
unit J674 Control unit for rear
right
information display
and operating
unit J649
MOST busBluetooth
TM
LIN
LIN

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LOCAL INTERCONNECT NETWORK
Electrical System
The familiar CAN bus (two-wire bus) is
supplemented by the following bus systems:
– LIN bus (single-wire data bus)
– MOST bus (optical data bus)
– Bluetooth
TM (wireless data bus)
LIN bus
LIN stands for Local Interconnect Network.
Local Interconnect means that all control
units are located within a limited structural
space (e.g. roof). This is also referred to as
"local sub-system".
Data are exchanged between the individual
LIN bus systems in a vehicle by one control
unit in each case using the CAN data bus.
The LIN bus system is a single-wire data bus.
The wire has a basic colour (violet) and a code
colour.
The wire cross-section is 0.35 mm
2. A screen is
not necessary.
The system permits data exchange between
one LIN master control unit and up to 16 LIN
slave control units.
SSP282_031
Design and operation of the LIN bus
are described in SSP 286 – New data bus
systems.
Diagnostic connection Data bus diagnostic
interface (gateway)
LIN master
LIN slave 2 LIN slave 1
Diagnosis CAN

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Media Oriented Systems Transport
R
The name of this data bus system is derived
from "Media Oriented Systems Transport
(MOST) Cooperation". This is an association
formed by various motor vehicle
manufacturers, their suppliers and software
companies with a view to developing
a standard high-speed data transfer system. MOST bus
The term "Media Oriented Systems Transport"
signifies a network featuring media-oriented
data transport. This means that, in contrast to
the CAN data bus, address-oriented
messages are transmitted to a specific
receiver.
This technique is used in Audi vehicles for the
transfer of infotainment system data.
The infotainment system offers a wide range
of modern information and entertainment
media. In addition to the familiar CAN bus
systems, use has been made for the first time
in the Audi A8 ´03 of an optical data bus
system.
SSP282_034
Design and operation of the MOST bus
are described in SSP 286 – New data bus
systems.
System manager
Sound system
DisplayOperating unit