Ok SL I am installing a new head unit. I have researched this topic and found may answers for what I am doing except for one question. I bought the Scosche wiring harness part#TA02B for Toyota 87-up. There is only one problem or concern really. There is an extra ORANGE wire that doesn't match up to the wiring harness of my Sony head unit. It is a Sony CDX-GT100. Not sure if that helps. But I just want to know if the ORANGE wire is ok to leave alone or if it needs to be spliced into another color or what??? Any help would be much appreciated!!! Thanks in advanced!

 

Thats the Illumination wire. Just cap it off if you don't have a matching one.

Some radios use that wire to dim the display a little bit when headlights are turned on

 

O sweet. Thanks for the help man. Glad I got that figured out.

 

cap any orange wire on there. There might be two if I remember. If you connect them they end up burning out the display over time.