A diode ? Why ? hook the relay's coil in // with the lights, that all No matter what amperage flows thru the light, a 12v Car relay will just suck 200mA more.
The small blue box is a pushbutton switch that carries 12v constant. When pressed it powers the coil. The diode stops the reverse lights from coming on (as far as I can tell, I already asked about this and people said it was fine but Im not expert)
Automatic video switching for a reverse camera
I have a 1n4001 diode and a 1amp spdt relay and I have the irking feeling that theyre going to go up in smoke
Any diode will work and any 12V relay will work unless the relay is draw more amp than the diode and/or the reverse circuit. The reverse light and switch is driving the relay so that is not much of a draw to the existing reverse circuit.
You are fine with that 1N4001 and any standard automobile relay.