Mcbtuba

I bought a retrosound radio to replace an older tape deck. The previous owner had shredded the old harness but I mostly got it back to stock. Hooked up the blue 12v constant, ground, and speakers for both sides. It requires an additional power for illumination. I can’t seem to figure out ignition switched 12v, so the radio doesn’t turn on. I have a Red-blue, and a green-white left. Checked fuses and still not getting anything on the voltmeter when ignition is on for either wire. Wouldn’t be surprised if it’s a me problem, but the frustration is rising. Thank you!