Info:- Headunit wiring for passive audio system

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After struggling with mine for a while I thought I'd do a little "How To" for other people. Mines a Rev3 95 Turbo with a passive sound system.

It's fairly straight forward, it's just the electric aerial I got stuck with and all the wiring diagrams I've found seem to be for the active system and all wire colours are completely different to mine.

Here's how it's done:

You should find the following wires in the cars stereo loom:


  • Yellow / Black / Red / Aqua / Pink / White / Purple / Blue
  • Front Passenger speaker: Pink + Purple -
  • Front Drivers speaker: Aqua + Blue -
  • Rear Passenger speaker: Yellow + Black -
  • Rear Drivers speaker: White + Red -

Power wires:

  • Grey ---- This is a switched Ignition +12v
  • Blue/Yellow ---- This is a constant +12v
  • Brown ---- This is an Earth

Electric aerial command wires

  • Black/RED ---- This needs connecting to your stereos ATT (The wire that goes live when the radio is switched on)
  • Pink/Blue ---- This needs connecting to the switched ignition +12v

Green ---- This is the auto dim command wire and goes to 12 volts when the side lights are switched on. It is the feed from the side lights/instrument illumination. If you test it with a multimeter it will show as an earth but if you switch sidelights on it shows 12v. A hint - if checking for earth connections, also check for voltage with the lights on as the lamp filament is very low resistance less than 1 ohm. This connection will happily act as an earth until you turn on your lights when it promptly blows the sidelight fuse. Use this only if your head unit supports the display dim function

That's basically it. It's very vague I know, it's mainly for people like me that struggled with making the electric aerial go up and down.

The fuses that might be blown in the process are:

  • Constant +12v "Dome" fuse
  • Ignition +12v "Rad & Cig" Fuse 
  • Ignition +12v ECU - IG" Fuse

All wires should be tested with a multi meter before any connections are made, to see if they do the appropriate function. This is just a guide to how I wired mine in. Yours may be different. If you don't know what you're doing, take it to a pro!

Hope this helps some people


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