Audi A6 2005 - Electrics Manual

326
All rights reserved.
Subject to
technical change.
Copyright
AUDI AG
I/VK 35
Service.t[email protected]
Fax [phone]
AUDI AG
D 85045 Ingolstadt
Technical release 01/04
Printed in Germany
A04.5S00.09.20
Audi A6 ‘05 – Electrics
Self-Study Programme 326
Vorsprung durch Technik www.audi.co.uk Service Training

The new Audi A6 – the most progressive vehicle
takes the lead.
The new Audi A6 consistently adopts the highly
networked electronic architecture, which is already
used in the Audi A8. Overall, new technologies allow
the A6 to match up with its "model" vehicle, the Audi
A8. Features, which were previously reserved or
luxury vehicles, are now also available in the top-
class segment.
In combination with these diverse capabilities,
the underlying technology has, o course,
been enhanced considerably.
The use o the most modern network technologies,
such as CAN, LIN, MOST and Bluetooth, and the
related distributed vehicle unctions signals the
arrival o a new generation o vehicle electrics in
this class.
Some o these are sa ety-related eatures, such as
the combined rain/light sensor or the pivoting
cornering headlight. Com ort eatures o the top
class, such as the MMI operating system or
sophisticated unctionalities or the mobile
baseplate, which is available ex-works, are part and
parcel o these new saloons.
The new Audi A6 has everything that is needed to
become the Number One model in the top-class
range.
It combines many di erent, attractive components
to orm one unit. Design and per ormance go
hand-in-hand. The new Audi A6 will take over
as the most progressive vehicle.
The Audi A6 – the most progressive vehicle takes the lead
Number One: With Design & Per ormance

NoteRe erence NoteRe erence
Control unit installation positions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Bus topology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Installation positions of fuses and relays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Overview
Convenience electrics
Control unit for power management J644 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
ccess and start authorisation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Immobiliser and component protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
External lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Control unit in dash panel insert J285 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Control unit for on-board power supply J519 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Control unit 2 for on-board power supply J520 . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Central control unit for convenience system J393 . . . . . . . . . . . . . . . . . . . . . . . . 55
Door control units J386 - J389 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Control units for seat adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Infotainment
Multimedia interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
ntenna systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Control unit for front information J523 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Sound systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
vailable telephone systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
The Sel -Study Programme provides in ormation on the undamentals o design and unction o new vehicle
models, new vehicle components or new technologies.
The Sel -Study Programme is not a Workshop Manual!
Speci ied values serve only to make the in ormation easier to understand and relate to the so tware version
that was valid at the time the Sel -Study Programme (SSP) was created.
For maintenance and repair work, please make sure to use the current technical documentation.
Contents

4
Overview
1 Auxiliary heating control unit J364
2 Control unit or ABS with EDL J104
3 Control unit or distance control J428
4 Transmitter unit in wheel well or tyre pressure
monitoring, ront le t G431
5 Control unit or on-board power supply J519
6 Door control unit, driver's side J386
7 Control unit or access and
start authorisation J518
8 Control unit in dash panel insert J285
9 Control unit or steering column electronics J527
10 Control unit or telephone, telematics J526
Telephone transmitter and receiver R36
11 Engine control unit J623
12 Climatronic control unit J255
13 Control unit or seat adjustment with steering-
column adjustment memory J136
14 Level control unit J197
Control unit or headlight range control J431
Control unit or tyre pressure monitoring J502
Control unit 2 or onboard power supply J520
Control unit or display and operating unit or
ront in ormation J523
Data bus diagnosis inter ace J533
Antenna read-in unit or keyless access
authorisation J723
15 CD changer R41
CD ROM drive R92
16 Door control unit, rear le t J388
17 Airbag control unit J234
Control unit installation positions

5
18 Rotation rate sensor 202
19 Door control unit, passenger's side J387
20 Control unit or seat adjustment with memory,
passenger’s side, J521
21 Door control unit, rear right J389
22 Transmitter unit in wheel well or tyre pressure
monitoring, rear le t G433
23 Radio receiver or auxiliary heating R64
24 Control unit or navigation with CD drive J401
Control unit or voice input J507
Digital sound package control unit J525
Radio R
TV tuner R78
Digital radio R147
25 Transmitter unit in wheel well or tyre pressure
monitoring, rear right G434
26 Parking aid control unit J446
Control unit or trailer detection J345
27 Central control unit or convenience system J393
28 Control unit or electric parking and
hand brake J540
29 Control unit or power management J644
326_146

6
Bus topology
Overview
NOX sensor
J583
Rotation rate sensor
G202
Seat occupied
recognition
J706
Power module
or le t headlight
J667
Power module or
right headlight
J668
Level control
J197
Electric parking
and hand brake
J540
Headlight range
control
J431
Automatic
transmission
J217
Airbag
J234
ABS with EDL
J104
Engine electronics 1
J623
Diagnosis connection
T16
Control unit in dash
panel insert
J285
Distance control
J428
Data bus diagnosis
or data bus
J533
Door control unit,
driver’s side
J386
Door control unit,
passenger’s side
J387
Door control unit,
rear le t
J388
Door control unit,
rear right
J389
Seat adjustment
with memory
Steering column
adjustment
J136
Seat adjustment
with memory,
passenger’s side
J521
Trailer detection
J345
Steering column
electronics
J527
Multi- unction
steering wheel
J453
Steering-angle
sensor
G85
Power management
J644
Auxiliary heating
J364
Parking aid
J446
On-board power
supply 2
J520
Access and
start authorisation
J518
On-board power
supply
J519
Centr. contr. unit or
convenience system
J393
Climatronic
J255
Tyre pressure
monitoring
J502

7
326_027
Display and
operating unit or
ront in ormation
J523
Tel e ph one
transmitter and
or telephone
R36
CD changer
R41
Digital
sound package
J525
Switch or
access and
start authorisation
E415
Antenna read-in
unit or keyless access
authorisation
J723
Wiper motor
J400
Sensor or rain and
light detection
G397
Passenger
compartment
monitoring
G273
Alarm horn
H12
Fresh air an
J126
Re rigerant pressure and
re rigerant temperature
G395
Tra nsmitt er,
ront le t
G431
Transmi t ter,
ront right
G432
Transmitter,
rear le t
G433
Transmitter,
rear right
G434
Antenna, rear
R96
Tel e p ho n e /
telematics
J526
Handset
or telephone
R37
Navigation
with CD drive
J401
TV tuner
R78
Radio module
R
Voice input
J507
MOST bus
CAN Instrument cluster
CAN Diagnosis
CAN Drive
CAN Convenience
CAN Distance control
LIN bus
Various sub-bus systems
Wireless transmission
– Bluetooth signal

8
Overview
Installation positions of fuses and relays
1 E box in radiator tank, le t
2 Relay and use holder behind
dash panel, le t
3 Fuse holder in dash panel, le t
4 Main use carrier in radiator tank, right
5 Fuse holder in dash panel, right
6 Relay and use holder in the boot, right

9
326_148

10
The basic design o the control unit or power
management is the same as the control unit used in
the Audi A8 ‘03.
It is installed in the boot well, next to the battery.
This control unit has been adapted or use in the
Audi A6 ’05 in that it now has revised so tware,
which shows the battery condition rather than the
battery charge level in the MMI display.
Furthermore, the diagnosis tester can be used to
read out history data, i.e. data relating to the
condition o the on-board power supply in the past.
Convenience electrics
Re erence
The basic unctions o the control unit or power
management J644 are described in the SSP 287.
Battery condition
The battery condition indicates how e icient the
battery is. The e iciency is determined rom the
battery charge level and the ability to start.
Advantages o the battery condition:
– The cut-o stages can be allocated directly to the
battery condition.
– The messages in the central display o dash
panel insert J285 always appear or the same
battery condition reading.
– A 100 % display indicates that no cut-o stage
will be set the next time the engine is switched
o .
326_072
User Car On-board manual
Battery condition
Systems Maintenance
Control unit for power management J644
326_094