I have a 13 Fx4 with Sony and nav and I can't for the life of me find a 12v key on remote signal to turn on my JL SSI or amps. I have the SSI all wired up under the console but nothing on the factory amp provides a switched 12v signal. Anyone have any insight here... I'm stuck!

 

If I recall correctly, the amp turn-on signal for the factory amp is 5v, and that will work on many aftermarket amps.