I wired a car camera in my car. I grounded it to a screw on a large round black bit of plastic under the glove box. It worked. My camera was set on "truck setting", so if the power was less than 21volt, it would shut off, so I changed it to "car mode" where power was less than 11.6volt and it worked. Double check you don't have anything like that. I tried that. Didn't seem to work for me. Yea. I understand that. But apart from the one that is visible. The others were just too hard to get to without taking off the Glove Box. Anyways, decided to finally take off the glove box. 5 Minute Job, wasn't as hard as I expected. And grounded it against the bolt all the other components are grounded to. All good now Thanks Guys!