Need help installing aftermarket stereo in a 1987 winnebago chieftain?

I have tested for power with other things so that is not the issue. the issue is the red acc wire on the head unit. Idk where it goes and that's why it won't turn on because Idk where to put it. here are the color options on the vehicles wiring harness, although I have tried all of them and they don't... show more I have tested for power with other things so that is not the issue. the issue is the red acc wire on the head unit. Idk where it goes and that's why it won't turn on because Idk where to put it. here are the color options on the vehicles wiring harness, although I have tried all of them and they don't work. lime green, purple, yellow, red, white and blue. maybe there is another way to hook it up to the ignition wire please help. thanks
2 answers 2