I've been wanting to add backup lights to my TT for several years now. I've read every single thread here & on other sites, my plan is to mount 4 LED flood lights, 2 on the rear bumper of the TT facing outward & 2 more in front of the TT tires facing outward.I have verified my 7 pin is hot in reverse & the yellow "7 pin wire" is run back to the junction box where the trailer lights are conected to the umbilical cord.I want them to come on when in reverse & be switch activated so that they stay on while unhitching/leveling.I know I need to wire in a relay & I've done a bit of research on it & have a pretty good idea on how to do that, but my main question is which leg of the relay does the switch get wired into The 30 or 86?The one thing I haven't found online is a "accurate" diagram of how to wire in reverse lights, using the 7 pin for power aswell as using the TT batteries for power along with using a switch "REV, off, on"One other thing I came across recently was adding a "diode" inline on both the 7 pin wire & on the hot wire from the battery to prevent backfeeding?Thanks, LeeP.S. I use magnets & towels to cover the tail lights on my truck.

Safety lights fall under US DOT regulations so it behooves one to check with them first before adding such lights.This may void your safety inspection...Only certain lights can be on the rear and front of towed units...You might get away putting them on the sides up high to the rear of the trailer...What you don't want is invest some monies into these kinds of lights only to have to remove them when it becomes inspection time. Talk to the JEEPS guys in California about adding lights...Not saying it can't be done but one should check on the requirements first. Even the lens of these light have to have DOT stamp approval numbers on them...Just saying...Roy Ken

Positive to switch, switch to 85, 86 to ground. Positive to 30, 87 to load.

And leave 87a alone. But, the switch won't keep the lights on after you disconnect the umbilical. For them to stay on after unhitching, you need a 12v hot to a switch to the lights that does not run through the relay, OR, a 12v hot to a switch to the relay on 85 when you are unhooked.However, your best solution is to forget the umbilical and a relay completely. Run from the trailer battery for a 12v hot to a switch to the lights. When you need them on, get out of the truck and hit the switch. When you are done, hit the switch again.

sfpcservice wrote:Positive to switch, switch to 85, 86 to ground. Positive to 30, 87 to load.Where does the wire from pin 7 connect?I would assume it goes to the switch then to the relay leg 85? The same goes for the positive wire from the battery, to the switch then to leg 30 correct?As far as the switch goes, what I am going to use is a SPDT (Single pole double throw) marine grade toggle switch. It powers 1 of 2 circuits at a time (REV on, off, TT battery on) in order to be able to turn the lights on with the truck out of reverse.Thanks, Lee

You absolutely want a relay to control the lights. I did not see if you posted the size of the lights you plan to add. If they are smaller lights plan on at least 1 amp per light. The problem I see with your plan is adding front lights to the trailer. Backup lights point backward. You would have to check your state laws on adding forward facing "backup" lights. Some relays have two separate triggers. One of them would be required to activate the lights. The Diodes allow one way voltage. Expect the diode to drop the voltage by .5volts. Wire the diodes on the trigger or control side of the relay. This allows maximum voltage to the lights. Be sure to fuse the power. I would add a fuse before the relay. If your two lights draw 1amp each, use a 5amp fuse for two light protection. I would add two separate circuits. One wired to the truck for rear facing backup lights. Another separate circuit for forward facing clearance lights. Have you considered a wireless remote control system? Not expensive to purchase. Have the rear facing backup lights wired to the truck and the wireless system. Either could engage the lights. Wireless switch #2 to the forward facing clearance lights. If you have extra wireless control circuits use #3 to control clearance lights under the stairs. Have #3 lights pointed downward to avoid glare. As you approach the trailer at night you could click on #3. Circuit #4 could point to some dark blind spot? Don't use expensive lights. Do buy an extra for replacement. This allows the future replacement to match the current lights. I use Kawell lights from Amazon. They are cheap and easily replaced. No idea if they are the best. They have worked for me. I also included a video of my Dodge. The lights are a combo of the included link and another style from the same manufacturer. I have many of these lights on my offroad Jeep. Kawell from AmazonMy towrig clearance lights.

Lee185

Explorer

Aug 22, 2016

Adding backup lights, Wiring help needed.

I've been wanting to add backup lights to my TT for several years now.

I've read every single thread here & on other sites, my plan is to mount 4 LED flood lights, 2 on the rear bumper of the TT facing outward & 2 more in front of the TT tires facing outward.

I have verified my 7 pin is hot in reverse & the yellow "7 pin wire" is run back to the junction box where the trailer lights are conected to the umbilical cord.

I want them to come on when in reverse & be switch activated so that they stay on while unhitching/leveling.

I know I need to wire in a relay & I've done a bit of research on it & have a pretty good idea on how to do that, but my main question is which leg of the relay does the switch get wired into The 30 or 86?

The one thing I haven't found online is a "accurate" diagram of how to wire in reverse lights, using the 7 pin for power aswell as using the TT batteries for power along with using a switch "REV, off, on"

One other thing I came across recently was adding a "diode" inline on both the 7 pin wire & on the hot wire from the battery to prevent backfeeding?

Thanks, Lee

P.S. I use magnets & towels to cover the tail lights on my truck.

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Adding backup lights, Wiring help needed.

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