Radio Wiring

Ti Kan ti at
Sun Dec 8 18:39:06 EST 2002

Cade Carvell writes:
>   I finally purchased a new radio, since mine was stolen.  Anyway, I was
> looking through the Bentley, 97.294 (for my 87 4kq).  And either I can't
> read it, or I have other things that were ripped out of the car.  I see
> 4 larger green wires (in my car), that don't appear on this guide at
> all.  Plus, looking at the diagram, I have no idea which is powered
> source, and which are for memory.  After I get that straightened out,
> determining speakers shouldn't be to hard.  I did notice that they use
> all black for front speakers, how do I determine polarity, if all four
> wires are black?

I presume your previous radio was a stock Audi Rothenburg (which is
what US 4Kq models come with).  This radio does not have separate
wires for power and memory.  The radio is "always powered" (as you
no doubt know) and can be turned on without the ignition on.  If you
disconnect the battery or power to the radio, the station preset
memory is lost.  This power goes to pin 2 on the radio connector.

The radio does have a separate illumination power line (pin 3 on the
connector), which is connected to the dash lighting circuit.  When you
turn on your parking light or headlight, the radio face illumination
comes on with the rest of the instruments, A/C control panel and
ashtray light.

As for the front speaker wiring, you can tell whether the speakers
are in phase simply by listening.  Play a mostly mono recording,
set the fader all the way to the front.  Position your head in the
middle between the two speakers.  If the sound seems to come from
inside your head, then it's wired correctly.  If the sound appears
unfocused, then one side is out of phase.  If that was the case,
set your balance control all the way to one side, and the fader
to the middle.  Now position your head between the front and rear
speakers and listen to that side, and then change the balance to
the other side and compare.  The side that sounds "focused" has
the correct polarity.

If your previous radio was not an Audi unit, then it's possible that
the wiring has been modified, so my description may not apply.

2003 A4 1.8T multitronic
2001 S4 biturbo 6-sp
1984 5000S turbo
1980 4000 2.0 5-sp
    ///  Ti Kan                Vorsprung durch Technik
   ///   AMB Laboratories, Sunnyvale, CA. USA
  ///    ti at

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