does any body know where i can get a circuit diagram for the audio system for a 89 mk 3<br><br>i am after the diagram for the radio/cd/tape deck<br><br>i am converting between a normal tape deck to cd and amp but cannot find a diagram..<br><br>thanks<br>Steve 89t<br>(member of UK Supras)

Perhaps local dealership? I dunno. If you can't get one, you can easily identify your tape player wiring harness with a multimeter. If it comes to this, let me know and I'll help you out.

Thanks for the reply but dealers in england are rubbish when you have an old supercar like these but all i need to know now is which pin if any does the radio take the signal that the lights are on.

Okay, you still have a couple of options. Go to www.crutchfield.com and see if you can order a diagram from them. If that fails, you can go to www.caraudioforum.com , register, and ask your question there. There must be SOMEONE there that has worked on a Supra. If all that fails, you can still do it yourself with a multimeter...<br><br>Finding the illumination...<br>This power wire only has power when the lights are turned on. If the lights are off the illumination will read as a ground and may also be found as follows. Set the multimeter to [ohms] and put the black probe on the ground of the battery. With everything turned off as you probe the harness you will find two wires that read continuity to ground. Turning on the lights will cause one of the two leads to no longer show continuity to ground. This wire that changes is the illumination. The other lead is the ground wire.<br><br>As you can see, this is easily the most annoying method, but I thought I'd post it just in case all your other options weren't helpful.<br><br>Good luck!