06d, I didn't think it worked like that. On startup, the HU sends power to the camera and looks for a video signal (we'll ignore the orange wire for now . If it sees a signal it knows a camera is there and when you put the car in reverse, it displays the signal. No signal on startup, no display of signal when car is put in reverse. That is what I think is stopping James4455 system from working. His camera is getting power from the brake lights which are off at startup. One prius owner just connected up the video wires and got power from the wiper motor and it worked. The down side is the camera is powered on when ever the car is on. There is a time limit for the camera check and I wonder if you turn the car on and quickly put it in rev if the HU would still be doing its check and see the camera signal.
James4455, Sorry to hear that you are still having trouble to get the backup camera working. May I suggest You return and get refund from BestBuy for that camera and just get the "plug and play" kit. The one I got come with instruction and connector for the HU. As long as the tech could open some panel and put them back, they could do the work and without worry about where to get the 12v power for Camera.
I got a quote from a shop that specializes is hybrids, mainly prius, it was 350.00 installed and that includes the camera from Toyota. That's if you have a touch screen LCD HU already. I was told by the sales person most options can be added elsewhere for about half of what the dealerships charge.
Just curious to know if standard back-up camera on 2015 Prius Two can be modified to show video when the gear is in Drive. As all of you know, the Prius have very restricted rear view through the split glass on the back. It would be very nice to be able to check the rear view camera while you are driving.
Toyota Prius Turn Signal / Hazard Rear Camera Activation Kit w/ Navigation Override - All Models - PriusChat Shop