Hello,
I need help.
I have mounted aftermarket Android head unit to my Mazda 6 - 2005 wagon and camera with wireless transmitter and receiver for video signal.
Everything works fine except that I have to find trigger wire with 12V current in front of the car to connect it to the screen.
At the tail of the car, between yellow/red wire and ground, which goes to reverse light, I can measure 12V when lights are on, BUT on the same wire when I track it to the front of the car there's no current.

Can you please help me how to get 12v near driver side kick panel?

 

Just run a wire from the rear up to the front.