Im trying to install a Boss 720ca head unit into a 1999 nissan sentra.

I have found the color codes and to my knowledge have everything wired up correctly, the head unit's power on button lights up, but does nothing when pressed. When the front panels removed there is also a flashing red light on the main unit.

im going to check with a multimeter and post up the results and i will also check the ground...

anyone got any other advice on this subject?

 

Possibly a theft code? I'm not familiar with Boss products, so does the manual say anything? Is it new?

 

well i determined the problem, the 12 volt constant wire is dead, i have to figure out why now.. for a temporary fix it just hooked both wires up to the 12v ignition wire..

but when the car is shut down i loose all my presets..

 

Run a wire to the fuse panel or straight to your battery. This can be a permanent fix for you. I still would figure out why there is no 12v+ (not that I need to tell you, I'm sure). Did you meter all the wires or just the 12v+ on the harness?