1995 AUDI A4 radio

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Radio systems

General information


CAUTION!

Before working on the electrical system:

Determine the correct coding for the anti-
theft radio.
Disconnect the battery Ground (GND)
strap.

Note:
After re-connecting the battery, activate the
vehicle's electrical equipment (radio, clock,
power windows, engine) according to the owner's
manual.
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Notes:

A new generation of the radio is being used for
model year 1998. The "Delta" radio will be
replaced by the "Concert" radio which has On
Board Diagnostic (OBD) capability.
When addressing customer complaints, it is
absolutely necessary to know the functions and
the operation of the radio system.
For additional information:

Radio operating instructions

When retrofitting, repairing or
troubleshooting:

Electrical Wiring Diagrams, Troubleshooting &
Component Locations

Radio installation instructions
Repair Manual "Body Interior" contains detailed
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installation instructions, e.g. removing and
installing trim.
All radio systems are equipped with anti-theft
coding.
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Retrofitting radio systems

The connectors on the factory-installed radio
wiring harness are designed for genuine Audi
radios.
Radios with different types of connectors must
be installed using adapter wires.

CAUTION!

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).
Vehicle malfunctions may also occur if the
vehicle speed sensor signal wire is connected
to radios supplied by other manufacturers.
If a non-stock radio is installed ("Concert" m.y.
1998 ) it can have a negative effect on the
antenna amplifier. The original Audi radio units
supply power to the antenna amplifier through
the center wire of the HF cable.

Retrofitting CD systems
The wiring for the CD changer is installed in the
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vehicle during production. The connecting cable
can only be used with original Audi CD
changers.
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Radio system, overview ( m.y. 1997)


"Delta" radio system
Multi-pin connectors I, II, III (on back of radio), terminal assignments
Note:
Terminals which are not listed are vacant/unassigned. 1 - Rear window antenna with antenna amplifier
2 - Bass speaker in front door trim (bottom)
3 - Mid-range/treble speaker in front door trim (top)
4 - Broad-band speaker (active with double amplifier) in parcel shelf (left-
rear)
5 - Broad band speaker (passive) in parcel shelf (right-rear)
6 - CD changer (optional) in luggage compartment (left-rear)

20-pin connector I
1 - Line out, left-rear
2 - Line out, right-rear
3 - Low frequency Ground (GND)
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8-pin connector II (brown) 6 - Switched positive supply (B+) for active speaker
8 - Clock signal
9 - Data signal
10 - Enable signal
12 - USA coding
13 - CD bus data (CD changer)
14 - CD bus clock (CD changer)
15 - Ground (GND) for (CD changer)
16 - Power supply (B+) (continuous)
17 - Switched positive supply (B+) for CD changer
18 - Low frequency Ground (GND) for CD changer
19 - Signal wire for left channel (CD low frequency-L)
20 - Signal wire for right channel (CD low frequency-R)
3 - Speaker line, right-front (+)
4 - Speaker line, right-front (-)
5 - Speaker line, left-front (+)
6 - Speaker line, left-front (-)
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8-pin connector III (black)
1 - Vehicle speed sensor (Gala)
2 - Low frequency mute switch (telephone system)
3 - Terminal 30
4 - Terminal 86s connection for ignition key switched on and off (S-
contact)
5 - Switched positive supply (B+) for antenna amplifier
6 - Illumination (terminal 58d)
7 - Terminal 30
8 - Ground (GND) (terminal 31)
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