Reversing camera wiring *solved*

[sssgsr]

Need power from reverse light for a reverse camera. Its only about max 0.5Amps for camera and screen. When trying to get power from the tiny cables in the rear lamp there is a BIG WARNING LABEL wrapped around the cables,
 "DO NOT DRAW MORE THAN 10 MILLIAMPS FROM REAR LAMP CABLES OR RISK SERIOUS INCIDENT"  

Is 0.5A is within error margin? i mean one 25W lamp equals 2Amps. Can the CAN system be faulty if i connect? Someone solved similar problem? Even using a relay would draw more than 10mA.
Or can you get into left rear trim panel and find something better to get power from? 

2015 Berlingo van

[Gadgetman]

0.5A is 500milliAmps, so yeah, pulling that power from the CAN bus will cause issues.

The electronics used to connect up 3rd party wiring looms for trailer hitches is designed to solve just this issue.

[sssgsr]

Was not much under trim panel. Combination lamp cables just go forward. Would there be tow bar prep? my next projekt...too bad.

But would be very easy to get wire from right side trim panel 12v socket, and using a relay and tap into cable for reverse light. But this will cause problems?
Or easier, replace reverse lamp with LED (about 5w). Lamp is 21W so I got 16W left, wich is over 1Amp. Maybe also with a relay.
Surely not first one to do this?

[sssgsr]

Solved. Cable with 12v feed from cig socket rear with a additional fuse then to relay. Changed reversing lamp for cheap led just to be sure and then I steal signal from cable to reverse lamp and connected to relay. Works great. Im sure I could have kept 21w lamp, I believe the big warning is not to now draw cable directly from lampcables to consumer (for ex tow bar electrics).
When it goes into eco mode (ignition on engine off) after a short while it goes black but thats fine.

[jimlee103]

Solved. Cable with 12v feed from cig socket rear with a additional fuse then to relay. Changed reversing lamp for cheap led just to be sure and then I steal signal from cable to reverse lamp and connected to relay. Works great. Im sure I could have kept 21w lamp, I believe the big warning is not to now draw cable directly from lampcables to consumer (for ex tow bar electrics).
When it goes into eco mode (ignition on engine off) after a short while it goes black but thats fine.

I am little confused and new to car electronics. I watched a video that said I could just tap into the reversing light power but guessing now that is a no no. 

Could you explain in a little more detail how the assemble works. 

Here is where I am: I need power to the camera which is linked to the reversing light so the stereo will know when the camera feed needs to show and so the camera is not on all the time. Its a 12V camera so I need power from the the 12V cig socket in the back. I was going to use to T taps to connect to the cig lighter but how do I then connect to the reversing light? 

Thanks in advance. I have a berlingo Van 2010. 

Jim