I have added a back up camera to my stereo andthere is a reverse wire on the stereo that onnects to the car to tell the stereo to turn the camera on. I could connect to the + at theback up lights,but I amtrying not to run another wire to the rear of the car. Can someone tell me where that wire might be under the dash.

Thanks

 

That might be the best way. The car uses the PNP switch under the hood to turn the reverse lights on.