Anyone knows if there's a wire on the front (dashboard) that changes voltage on reverse?

I bought a wireless reverse cam and in order for the Pioneer radio to change automatically when on reverse it needs a wire connected to a reverse cable, I don't want to actually have to bring a wire from the back after buying a wireless cam.

 

Thanks!

If you can't find the reverse to pick it wire in the dash you should be able to pick it up in the harness running down the passenger side. Lift the door sill plates, the harness will be at under the carpet. Look at the rear signal light and see if you can determine the wire color for the reverse lights.

 

This is where I picked up the signal in two of my cars.