Why does my CD player not work?

[DAVE]

I have a 04 Civic. My aftermarket CD player stopped working about a month back. All of the fuses and wires are in good condition. I assumed CD player went bad. I bought a brand new one yesterday. I wired it up and installed it and it doesn't work either. What is my problem? The CD player isn't getting power.

 

[Mercuri]

Get a multimeter or a 12volt tester($2 at hardware/automotive store). Check the power on the yellow wire of your aftermarket harness. It should have 12volts at all time, even when the car is off. Next check the red wire, it should have 12volts only when the key is ON or in the ACC position. Now check your black ground wire, it should have no voltage ever. These are the only 3 wires your radio needs to turn on, the rest are speaker wires, illumination and remotes. If your yellow wire is not getting power, check the fuse panel on the driver side dash. There is also a bank of fuses under the hood, be sure to check these as well.