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Downloaded from www.Manualslib.com manuals search engine 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
Page 6 of 82
Downloaded from www.Manualslib.com manuals search engine 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
Page 68 of 82
Downloaded from www.Manualslib.com manuals search engine 91-59
Center Mid/High Range Loudspeaker -
R158-, removing
Removing
- Carefully pry off the cover -A- for sunlight photo sensor.
- Remove screw -B-.
- Disconnect electrical connection.
- Remove screw -1-.
- Detach defroster vent.
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication
Page 69 of 82
Downloaded from www.Manualslib.com manuals search engine 91-60
Installing - Remove bolts -1-.
- Swivel out loudspeaker and disconnect electrical connection.
- Install in reverse order of removal.
- Tighten bolts on loudspeaker to 2 Nm.
- Tighten bolts for the defroster vent and photosensor to 0.8 Nm.
Audi A4 Sedan 2002-2004, Audi A4 Avant 2002-2004, Audi A4 Cabriolet 2003-2004 - Communication