Intermittent problems can be impossible to nail down.
If these power wires are reversed, the radio will fail to work properly or at all.
It may be time toreplace the head unit.
Lifewire / Theresa Chiechi
Why Your Car Radio Won't Turn On
If your car radio won't turn on, there are a few things you'll want to check before you throw in the towel and buy a replacement.
