hard wire for cobra radar detector
 

I bought the hard wire kit for the cobra radar detector I have and I've tried connecting it directly to the battery and grounding near by and was unable to get it to power, so I recently tried connecting it to the cigarette lighter power and ground cables and can't get it to power still. am I doing something wrong??? I just wired a sound system by myself with no problems.... why can't I do this stupid cable!? help please!!

Has anyone tried this? any hints on where to connect it?