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Connect your RCA cable to the camera cord's video connector if necessary. Then, run it through your vehicle to the area by the fuse box. Depending on your vehicle model, you'll usually be able to do this by peeling back the automobile's headliner or side panels and pulling your cable through the exposed chamber. For certain trucks, you may need to run the video cable through the vehicle's frame rail. In most cars, you'll find the fuse box underneath the steering wheel. If you're installing an external monitor, first attach your device's included mount to the windshield by following the manufacturer's included instructions. Then, hook your monitor onto the mount. Most external monitors use a suction mount, though others may come with a more complex mounting system. For certain internal monitors, you'll need to clip the new device onto your current rear-view mirror. For others, you'll need to take off the mirror and slide your monitor into the pre-existing mirror mount. Some internal monitors may come with their own mounting system that you'll have to attach to the car's front windshield. If necessary, hook your monitor's power and video cable into the device. Then, route the cable from the monitor to the area next to the fuse box. If you'd like, use a trim removal tool to pop out the headlining panel directly above your windshield. Then, run your cable through the exposed chamber. After routing your monitor's splitter cable, connect the video end of the cable to your camera's RCA cord. Then, wrap the connected cords with electrical tape to hold them together. If your RCA and video cables have the same ends, you may need to purchase an RCA male to female converter cord. You can find these at most electronic stores. Connect your remaining bare wire cable to the backup monitor's power cord. Then, push the positive (usually red) end of the bare wire cable into the open end of a fuse tap. Finally, crimp the 2 cables together with a pair of pliers. A fuse tap is a small cable that converts a bare wire into a fuse signal. You can find them at most auto part stores. If you'd prefer, you can leave the bare wire cable off and connect your camera's power cable to a cigarette lighter adaptor. Then, plug this adaptor into your car's cigarette lighter receptacle for power. Locate your fuse box and open it up. Then, plug your fuse tap into an open fuse cell. If necessary, check your fuse box's lid or your vehicle's instruction manual to see which slots are open. After attaching your fuse, consider taping all your wires together using electrical tape to get them out of the way.
Route your camera's video cable to the front of the car. Fix external monitors to the front windshield. Attach internal monitors to the rear-view mirror or mirror mount. Run the monitor's splitter cable to the fuse box. Connect your monitor's camera cable to the RCA cable. Attach your monitor's power cable to a fuse tap. Plug the fuse tap into the fuse box.