Reversing light fault

Hello XK Owners,

I hope someone can help me. I have a 2008 XK 4.2 X150, and after trying to add a reversing camera (the existing one reverse light just not bright enough) I now don’t have neither the light or the camera. When putting the car in reverse the light comes on and goes right out, the camera turns on for a second then off again. I have just changed the battery for a brand new one as the old (possibly original) was a bit week - 11.7 Volts - unfortunately didn’t help. I also disconnected the camera (Auto-Vox M1) but that didn’t rectify the problem.

The car already had problems with the offside side lights that stopped working and even after checking the wiring we could’t find any faults. In that case I have connected the nearside and the offside lights together so now at least they are working…

I would really appreciate if somebody could direct me to what to check next.

Thank you in advance

Xander