I don't exactly understand how you connected your camera but I will try to explain with my limited knowledge of English how I connected mine.
The camera has a black and red wire and an RCA connector. The black goes to ground, the red to 12V+ in the rear light unit (reverse light bulb socket). The red wire that comes out of the RCA cable that transports the video signal to the front is not used.
At the front you have the same RCA cable also with a red wire I think. If so that red wire is also not used.
That should do the trick.
I hope I wrote it down in an understandable way
