On / off switch is on the power cord. it's a small black slider on the end of the plug that goes into the cigarette lighter socket.
When you say you're not getting red/green lights I presume you are talking about on the AUDIOnode warning device inside the car? That doesn't actually mean that your LPP is not getting power or working properly - it just means that you don't have the AUDIOnode switched on.
I suspect you'll find that the lpp is fine.