the blue wire is your remote turn on.It will connect to your power antenna lead on your stereo or a lead that will come on when you turn your key on.If you you connect it to something that comes on when you turn the key on,the amp will stay on anytime the key is on.If you connect it to your power antenna lead on your stereo ,it will only come on when your radio is on.I'm looking for this manuel.Do you have it?