Adding a switch to Reverse Camera

Adding a switch to Reverse Camera

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tfrezza

Original Poster:

1 posts

85 months

Tuesday 4th April 2017
quotequote all
Amateur alert!
I have a reverse camera installed in my van. At the moment, it's wired so that it draws power from the reverse light, so that when I go into reverse, it turns the camera on. All well and good, and it works. What I want to do is install a switch in the front of the van so that if I'm driving along, I can turn the camera on and see what's behind me. I have installed a switch and wired a constant 12v feed (stereo, will turn off with ignition) to it, then from the switch to the camera. The issue I have is that if I turn the switch on, the camera comes on along with the reverse light. Because of this, I think I need some diodes to control the flow so that the switch only turns the camera on and when it's off, the reverse light will power the camera instead. But I am unsure which diodes to get, as I believe they all different values. I know the following:
  • Reverse Light: 12v 21w (I'm assuming 1.75a)
  • 12v live feed to switch: (unsure of amps or watt)
  • Camera: 12v 130ma
I know how to wire everything (see badly draw image) but I am unsure which diodes to get... can you help?
I think I need one 12v 1a diode (for the camera) and one 12v 2a diode (for the reverse lights), if these even exist!
Do I need to know the amps from the 12v feed?
Thanks