I often arrive at campsites after dark and it's hard to see how to back in.
I'm wondering, can I tap into the reverse lights on my truck to energize a relay that will feed battery power to a light that I will mount on the rear bumper of the camper?
I guess what I need to know is will it hurt rob power from the reverse lights on my truck to energize the relay?

 

Hey silvers,

How long is your camper? Mine is 34 feet tongue to tail. I have to use a spotter because of the length. Some of the guys here in the FTE group pull even longer.

Now that I think about it, back bumber corners 45 degree from straight back might help.

Your relay thought is by the way the correct way to do it. You could even throw in a fuse in the mix and add alittle safety..

Good luck,

 

To trigger the relay (if your camper doesn't have white backup warning lights) run a wire from the center connector on the seven way plug. But you need a switch on the trailer so that it doesn't come on when you are on the road.

My thoughts are go from the trailer side end of the seven way cable - IT IS the yellow wire. Put a switch in the wall of the front storage compartment, on the inside somewhere. But up high so that stuff won't fall on it and turn it on.

Run from the switch, to a BOSCH relay coil and to ground on the other side of the coil.
Go from THE RV battery to a twenty or so amp self resetting breaker and then to the input contact on the relay.

Next run from the normally open contact to your lights, and there you have it.

1) The backup lights on the truck come on (regardless if your trailer has white backup lights or not) and the corner spots come on.

2) You have a breaker in place to protect the circuit.

3) You have an interrupt switch so that it doesn't annoy State Policemen.

You can also just wire a switch from the batteries in the RV to a breaker, and then on to the corner lights. I think I personally would rather have that, so that they stay on, but are only used when parking the rig.

I've already seen some coaches with what are called "DOCKING" lights, operated from a switch on the dash panel. They're white flood lights mounted on the sides near the back and close to the ground.

 

Brew, my camper is about 28' overall. We just bought it so i'm trying to get it ready for the spring.
Greywolf, I never thought about using the RV batteries for power, thats a good idea that will save alot of wire, thanks. You have a good point about using a switch so they will stay on also. One question though, why use a breaker instead of a fuse?
I really don't want to run wires inside the camper box either, I was hoping to keep everything on the frame rails.

 

If your trailer has back-up lights on it allready it's a no brainer. Yours must not going by your question.

I wouldn't even worry about splicing into the back-up light wire but would just wire them into a switch from the trailer battery. If your going to put them on a switch anyways your going to have to get out of the truck .

I would put a switch in by the battery and run one wire back along the frame rail to the lights .When you get to where your going have someone get out and flip the switch and your done. This way if you do need more light when loading or unloading you don't have to have the truck in reverse.

 

Your right. Thats exactly what I have decided to do. I just thought it would be nice to have them come on with my truck reverse lights but yall have changed my mind. Thanks guys

 

> I guess what I need to know is will it hurt rob power from the reverse lights
> on my truck to energize the relay?

That is how I do it. No, it will not hurt a thing. The wire coming from most Ford reverse switches is 14-16 gauge and is feed directly from a battery source. Many Ford trucks have a harness that comes from the transmission, to the harness that goes to the back and plugs in at the firewall near the master cyl. Interrupt it here, mount the relay and fuse under the hood.

What I do. Put a sealed fuse with a cover on the starter relay with an eyelet. Run the battery power to another Ford relay on the driver's fender across the radiator support. The fuse will protect from a short in case of an accident or wear. PLUS, if you want to work on something near the driver's side, you just unplug the fuse.

Then from the driver's relay, run power from the + terminal to a reg. relay mounted on the fender. That way if you run 12 gauge wire from the Bosch relay backwards you can draw up to 30 amps to power reverse lights both on the truck and on the trailer.

Plus, you can mount side marker lamps with 194 bulbs so it shines out on the sides too. A 194 reverse lamp on the side is not bright enough to blind people, but, bright enough to see objects so you do not clip something.

 

Self resetting breakers are only two to five bucks and can be mounted with a single self tapping screw and a cordless drill. They are small - they look like wire terminals.

But they do the job, and last for years.

 

ok well my trailer is 38' 5th Whell and have done just that. Use the truck 12v back power to run the coil of a relay for the extra back up lights. The lights run off of the trailer battery. Also have a switch in lower compartment to activate coil of the relay for when truck is unhooked. Have played with the placement of the lights and have a set just before the dual wheels so I can see them when backing up. Have a second set about 5' from the rear of the trailer. These help light up the area for the person in the back helping you back up.

 

The 7 pin trailer tow connector on your truck has a backup light pin. Just hook up to it.