Reverse Wiring Diagram

[76 MA Bronco]

I've put a reverse sensing system into my wife's 03 Escape that I bought off eBay. I traced the backup light wiring to the harness (Orange with a yellow stripe) and spliced it, ran the sensors in the bumper and it looks good...BUT...start it up and in P R N D 2 1, the system is on in all gears!!!! I know this is going to drive her nuts when she's in traffic. Does anyone know how the backup light is wired? Is there a relay that grounds it when in reverse? It looks like it's wired like an old Ch@vy, positive ground. Any help would be greatly appreciated...

[77redf250]

i'd start at the light bulb and follow the wire up or just run a wire right to the socket.