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Backup Camera with optional power source bypass switch

  1. Aug 26, 2015 #1
    I just installed a backup camera on my motor home , which is triggered by the reverse light wire. I would like to add a switch to the circuit so while I'm driving or just to be able to turn on the backup camera (using it as a rear-view mirror) without putting the vehicle in reverse. I probably need to add 1 diode to the backup light wire to prevent the backup lights from coming on when I turn on the camera using the additional switch (bypass). And will I need an additional diode to be installed on the bypass switch to prevent 12 volts traveling back to the manual switch as well? If I'm on the right track about all this, what size diode or diodes will I need?
  2. jcsd
  3. Aug 26, 2015 #2


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    No. "Size?" Voltage rating --- 12+ volts in principle --- in practice, diodes are cheap --- 50-100 covers transients; current rating --- you're not likely to have a clean heat sink for long if you go to the trouble of using one --- camera current times five or ten for a wire and forget installation.
  4. Aug 26, 2015 #3
    I'm not understanding what your telling (sorry). The power consumption of the camera is nil about .5 watts max, I'm not quite sure what the power consumption of the trigger is to start up the LCD screen. The unit is a kenwood Dx5120 which is a stereo/DVD player with the option for a backup camers
  5. Aug 26, 2015 #4


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    Can you just connect the camera to the general switched 12V for your motorhome? If it's that low power, there's not really a reason to shut it off when the motorhome is on...
  6. Aug 26, 2015 #5
    I could and probably will if I can't figure this out. I just like to take it one step further. Plus when the camera is on it interrupt the srereo/dvd. I guess it's the idea of always flipping the switch on and off. If you know what I mean.
  7. Aug 28, 2015 #6
    any diode will probably work....
  8. Aug 28, 2015 #7


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    Can't you just press the NAV button for a few seconds to turn on the camera and view it from the headunit. I've got a Kenwood 812 that works that way. The camera is powered from the ACC bus and the reverse wire is connected to the headunit to switch to that video source when triggered by the reverse wire.
  9. Aug 28, 2015 #8
    Thank you, Actually I figured it out all ready. I installed a 1N4007 and it works great. I remembered when I installed a remote starter in my wife's car there was a instance where a 1 amp rectifying diode was need too. At that time I purchased 20 of them because all of our family members wanted remote starters, so I have plenty of them to use.
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