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Discussion Starter #1
Hi guys. I am installing a rear view camera in my 2014 lwb 4motion and wired it to the reverse light on the left hand side but the voltage there is only 10.7 volts even with the engine running. That's not enough to power the camera on. I checked the tail light and only 11.5 volts. I connect a battery and all is well at 12.7 volts. What am I missing?
 

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try measuring voltage from the reverse light green wire to the body of the van. is it still low?
and on continuity check you have a nice low reading (0.00001 ideally) from the earth at the bulb holder back to the body of the van.
if the earth is ok then i'd be looking at the reverse light switch on the gearbox, assuming you have a manual
 

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Discussion Starter #5
Well I found out by accident while fiddling with the wiring and trying different things, the camera came on when the earth was the same for that and the screen. So I wired up the screen in the front and turned on the ignition and it all worked. BUT, when I started the engine, no video. Checked all the wiring again and the power feed to the screen and everything worked until the engine is running.
Powering the screen from the cig plug on top of the dash and the voltage is still on with the engine running. What is the problem now? Any suggestions appreciated.
 

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This is caused by the cambus pulsing the voltage for bulb failure, you need a relay with a switched live and use the green black wire to trigger it , that’s assuming you only want the camera on in reverse
 

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well I don't understand your explanation of how you got it to work, nor why it still doesn't work but if Letstryt5sgain suggests it could be because of the bulb monitoring system, just turn that off using VCDS and it should solve the camera problem, although you'll have to manually find out if a bulb fails in the future, other road users normally do that for me (y)
 

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Discussion Starter #8
Thanks guys for your suggestions. I think a relay will be easiest since I don’t have a windows computer. What else can I do with a VCDS that would make it worth buying a cheap windows machine. And will I cause myself more trouble when I start looking at what it can do? I won’t be able to help myself.
 

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Discussion Starter #9
Also, would wiring up a relay to that same green wire not cause the same problem? And if the canbus is recognising a problem, it is not turning off power to that light because both reverse lights are still on, so why not the camera? Or is it still something to do with the earth?
While you guys are sleeping on it, I have all day to play around.
 

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Use the green/black reverse wire as the relay trigger , find a 12v supply for the other side of the relay and then the output to the camera and radio will be a solid 12v , you will also need to earth the relay
 

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Discussion Starter #11
Thanks Letstry5again. That was to be my next move after playing around yesterday with better earth to the body for both camera and screen but still not working once I start the motor. Great picture though when ignition on and in reverse. I have also just ordered transmitter and receiver to save me running the video cable through somewhere. I am thinking the transmitter can go in the door and be powered from the same relay and the receiver possibly behind the dash. Will report on progress.
 
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