Truck rear wiring upgrade thoughts?

[ckupq]

So I bought my truck used Dodge two years ago. The previous owner had added a under tailgate brake light strip and cobbled wiring for a topper light and topper 3rd brake light. The tailgate strip still works, but the topper wiring doesn't. The plan is this summer to make all of it work and add some extra backup lights for when I am plowing. The first thought was to cut my 7-pin and wire in something like this to handle the extra circuits rather than crimps and gobs of electrical tape.

https://www.amazon.com/MICTUNING-Wa...efRID=V06ZYN9ZJVM686BAFN9F&tag=91812054244-20

I've heard this can also make things a wee bit finicky because of reasons when it comes to newer trucks. This is a 2005 Dodge 2500 for reference.

Has anyone done this on their rigs. I'm not looking for beauty, just to clean up someone else's hack job.

 

[lagunaMS]

My first step is always cutting the previous owner's shit out and starting fresh so I know it's done properly. Run a new wire from the battery to a switch inside the topper for a light. Solder in a new wire to the brake lights for the topper 3rd brake light. For the reverse lights I'm not sure if the extra lights will overload the factory reverse light wiring but you could do it with a relay setup I think.

 

[ckupq]

My first step is always cutting the previous owner's shit out and starting fresh so I know it's done properly. Run a new wire from the battery to a switch inside the topper for a light. Solder in a new wire to the brake lights for the topper 3rd brake light. For the reverse lights I'm not sure if the extra lights will overload the factory reverse light wiring but you could do it with a relay setup I think.

I'm right there with ya. The plan is to cut out the bad and replace with good. I wanted to tie in the brake lights to the 7 pin side of things being the taillights work fine. The reverse lights would be on a relay and would only use the reverse off the 7 pin for a signal. The inside topper lights I was going to run to the 12 wire on the 7pin because it is switched and doesn't come on unless the key is on. The box may be overkill, but meh.

 

[aczlan]

Something like this: https://www.amazon.com/CURT-56071-Vehicle-Side-Trailer-Extension/dp/B0031GHBU2?tag=91812054244-20 should let you tee into the power going to the 7 pin plug.\nIf you want a 3rd brake light you may need something like this: https://www.amazon.com/CURT-56196-2-to-3-Wire-Taillight-Converter/dp/B0046EKPHY/?tag=91812054244-20 or a relay.\n\nAaron Z

 

[ckupq]

Something like this: https://www.amazon.com/CURT-56071-Vehicle-Side-Trailer-Extension/dp/B0031GHBU2?tag=91812054244-20 should let you tee into the power going to the 7 pin plug.\nIf you want a 3rd brake light you may need something like this: https://www.amazon.com/CURT-56196-2-to-3-Wire-Taillight-Converter/dp/B0046EKPHY/?tag=91812054244-20 or a relay.\n\nAaron Z

So a $70 Y-cable instead a $10 box and some ring crimps?

 

[aczlan]

So a $70 Y-cable instead a $10 box and some ring crimps?

That box is not going to keep the salt spray out when you are plowing and its just going to corrode at the crimps (even if you use heat shrink crimps) and its going to be worth more than $70 if you have to crawl under there in the middle of a slushy parking lot for the 3rd time that night trying to get all your lights to work again so you can see when backing up. Or when you get rear ended because some idiot was following too closely and your brake lights didn't turn on when you hit the brakes.
If you want to splice it on the cheap, go to the junkyard and cut out that connector and a foot of wire on each side, then splice them together with heat shrink butt splices. Go up a size on the splices for the ones you want to tap into and add another wire on one side.
I wouldn't use that box anywhere it was going to get salty and I wanted the lights to work no matter what.
If you want to use that box up in the bed under your cap where it will be protected, sure. I would not use it under the bed to splice my taillights if I had another option.

Aaron Z

 

[posford]

OP: I've used a junction box like the one you linked on a flatbed truck, sourced from NAPA 10-12 years ago. Works well for what it is, the keys are tucking it up out of the way, using a sealant on the wires as they pass thru the grommet, and dielectric grease on EVERYTHING when you're done. This is in the northeast where there's plenty of salt and corrosion.

 

[A_G]

OP: I've used a junction box like the one you linked on a flatbed truck, sourced from NAPA 10-12 years ago. Works well for what it is, the keys are tucking it up out of the way, using a sealant on the wires as they pass thru the grommet, and dielectric grease on EVERYTHING when you're done. This is in the northeast where there's plenty of salt and corrosion.

ill second this