Audi A4 Sedan 2002 Use and care manual

91-1
Radio system
General information
CAUTION!
Before beginning repairs on the electrical
system:
Obtain anti-theft radio security code if
necessary.
Switch the ignition off.
Disconnect battery Ground (GND) strap.
On vehicles equipped with Audi Telematics
by OnStar , switch-off the emergency (back-
up) battery for the Telematic/Telephone
Control Module prior to disconnecting
vehicle battery. Use VAS 5051 Vehicle
Diagnostic, Testing and Information System
in mode "Guided Fault Finding" Page 91-
119 .
After reconnecting vehicle battery, re-code
anti-theft radio if necessary and check
operation. Also check operation of clock and
power windows according to Repair Manual
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication

and/or Owner's Manual.
After reconnecting vehicle battery on
vehicles equipped with Audi Telematics by
OnStar , switch-on the emergency (back-
up) battery for the Telematic/Telephone
Control Module. Use VAS 5051 Vehicle
Diagnostic, Testing and Information System
in mode "Guided Fault Finding" Page 91-
119 .
Note:
Further measures after reconnecting the voltage
supply:
Repair Manual, Fuel Injection & Ignition,
Repair Group 24
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication

91-2
Before troubleshooting or servicing, technicians
must be familiar with the functions and operation
specifics of the applicable standard or optional
radio system. Always read the radio owner's
manual and review all radio, tape player and CD
player/changer functions.
Notes:
When retrofitting, repairing or
troubleshooting:
Electrical Wiring Diagrams, Troubleshooting &
Component Locations
Radio installation instructions
For detailed instructions (e.g. removing and
installing trim panels):
Repair Manual, Body Interior, Repair Group
70
Wherever possible, only genuine Audi parts
should be used. Only then can trouble-free
installation and optimal reception be
guaranteed.
All radio systems have anti-theft coding.
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication

All Audi radio systems are encoded for the
instrument cluster in the convenience coding. It
is not necessary to enter the code when
disconnecting and reconnecting the power
supply, removing and installing the same radio
or removing and installing the same instrument
cluster.
Contact Corrosion
To minimize contact corrosion, only use
approved fasteners (screws, nuts, bolts, washers
etc.)
Where applicable, fasteners may have a special
surface coating recognizable by a greenish
color.
Coated fasteners must also be stored
separately.
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication

91-3
On Board Diagnostic (OBD)
Radio systems have extensive On Board
Diagnostic (OBD) capabilities.
The radio unit has a Diagnostic Trouble Code
(DTC) memory. If a malfunction occurs in one of
the components or wires which is monitored by
the system, a record of the type of malfunction is
stored in DTC memory. Use VAS 5051 Vehicle
Diagnostic, Testing and Information System in
mode "Guided Fault Finding".
Retrofitting of radio systems
The electrical connections on the factory-
installed radio wiring harness are designed for
genuine Audi radios.
Radios with different types of electrical
connections must be installed using adapter
wires.
When connecting the vehicle speed sensor
signal wire (on radios with the GALA function),
take particular care to avoid short circuits,
which could result in vehicle malfunctions (e.g.
in the engine management system).
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication

Vehicle malfunctions may also occur if the
vehicle speed sensor signal wire is connected
to radios supplied by other manufacturers.
When other radio units are installed it can have
an effect on the antenna amplifier, since the
original Audi radio units have a remotely driven
antenna (the voltage supply of the antenna
amplifier is driven via a center wire of the high
frequency cable). Use a remotely driven
adaptor parts catalog (vendor: Votex).
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication

91-4
CD equipment, retrofitting
The wiring set for the CD changer unit is in the
vehicle during production. The connecting cable
can only be used with original Audi CD
changers.
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication

91-5
Transport mode, deactivating
"Symphony" radio systems are disabled
(switched-off) when Transport Mode is activated.
This is necessary when vehicles are transported
over long distances or stored for longer periods
of time.
Audi A4 vehicles from 2002 are initially delivered
to dealerships with radio system in Transport
Mode, and must be deactivated before delivery
to the customer.
Use VAS 5051 Vehicle Diagnostic, Testing and
Information System in mode "Guided Fault
Finding".
Further information
Repair Manual, Maintenance, "Description of
Work"
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication

91-6
"Concert II" and "Symphony II" radio
systems (Sedan), component overview
1 - CD Changer Unit -R41-
Optional
In glove compartment
Removing and installing Page 91-48
Check wiring Page 91-50
2 - Center Mid/High Range Loudspeaker -
R158-
In instrument panel
Removing and installing Page 91-59
3 - Radio -R-
In instrument panel, center
Removing and installing "Concert II" radio
Page 91-44
Removing and installing "Symphony II"
radio Page 91-46
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication

91-7
4 - Amplifier -R12- (for rear loudspeakers or
BOSE power amplifier with "BOSE
sound system")
In right rear luggage compartment behind
side trim
Removing and installing amplifier for rear
loudspeakers Page 91-63
Removing and installing BOSE power
amplifier Page 91-65
5 - Bass Loudspeaker -R100-
Below rear shelf
Removing and installing Page 91-61
6 - Antenna Selection Control Module -J515-
Under rear headliner trim
Removing and installing Page 91-67
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication