CD changer AUDI A4 1999 B5 / 1.G Radio System Workshop Manual
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91-3
      
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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Page 5 of 45
vehicle during production. The connecting cable 
can only be used with original Audi CD 
changers.  
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91-4
      
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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91-5
 
    
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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91-7
      
"Delta" radio with BOSE sound 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 - BOSE amplifier in luggage compartment (left-rear)
3 - Bass speaker in front door trim (bottom)
4 - Mid-range/treble speaker in front door trim (top)
5 - Broad band speaker in rear door trim
6 - Bass speaker in parcel shelf
7 - 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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91-8
 
    
4 - Line out, left-front
5 - Line out, right-front
6 - Switched positive supply (B+) for BOSE amplifier
7 - BOSE coding
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) (CD changer)
16 - Positive 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)
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91-10
      
Radio system, overview (m.y. 1998  )
 
     
"Concert" radio (sedan)  
    
"Concert" radio (Avant)   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)
    
1 - Roof 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 (2-way) in rear door trim
5 - Bass speaker (subwoofer) in left-rear of cargo area under side trim
6 - CD changer (optional) in left-rear of cargo area under storage 
compartment
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Page 14 of 45
91-12
 
    
8-pin connector II (brown)  13 - Bus data in (CD changer)
14 - Bus data out (CD changer)
15 - Clock (CD changer) 
16 - Continuous positive supply (B+)
17 - Switched positive supply (B+) (CD changer)
18 - Low frequency-Ground (GND) (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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91-14
      
"Concert" radio with BOSE sound system 
(sedan)  
    
"Concert" radio with BOSE sound system (Avant)   1 - Rear window antenna with antenna amplifier
2 - Telephone speaker 
3 - BOSE amplifier in luggage compartment (left-rear)
4 - Bass speaker in front door trim (bottom)
5 - Mid-range/treble speaker in front door trim (top)
6 - Broad band speaker in rear door trim
7 - Bass speaker in parcel shelf
8 - CD changer (optional) in luggage compartment (left-rear)
    
1 - Roof antenna with antenna amplifier
2 - Telephone speaker 
3 - BOSE amplifier combined with bass speaker (subwoofer) in cargo 
area (left-rear) under side trim
4 - Bass speaker in front door trim (bottom)
5 - Mid-range/treble speaker in front door trim (top)
6 - Broad band speaker in rear door trim
7 - CD changer (optional) in cargo area (left-rear) under storage 
compartment
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Page 18 of 45
91-16
 
    
8-pin connector II (brown)  8 - Clock signal
9 - Data signal
10 - Enable signal
13 - Bus data in (CD changer)
14 - Bus data out (CD changer)
15 - Clock (CD changer) 
16 - Continuous positive supply (B+)
17 - Switched positive supply (B+) (CD changer)
18 - Low frequency-Ground (GND) (CD changer)
19 - Signal wire left channel (CD low frequency-L)
20 - Signal wire right channel (CD low frequency-R)
5 - Hands-free speaker (+) 
6 - Hands-free speaker (-) 
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