2004 Prius not starting

I've been having problems with my 2004 for a while. Over the past couple days I have replaced the hybrid battery pack and the 12 volt battery. When I press the foot brake and the power button still nothing but all the lights come on. This is getting to be very frustrating and expensive. I've done the procedure where you hit the power button twice and still all the lights are on. Any ideas are appreciated.