24v to 12v 7 blade for towing trailers

[Lantzj22]

As my title mentions, I’m looking into how to convert my 24v trailer wiring system that’s on my 89 m923A2 down to a 7 blade for my camper/boat and who knows what else I might tow.

I know there is an option for about $350-$400 online, I am curious if anyone else has done it, what you used and how. I’m really only looking to get lights, signals, brake lights as my commute is about a mile to the beach under 30mph so no need for brakes.

my thought (PLEASE correct me), is to use a 24v-12v step down on the power and ground, then wire up the 7 blade (or 4 pin depending what’s easiest) and the rest of lights. Do I need to have a step down converter for each of those wires or just power/grnd?
Thank you so much!

 

[98G]

Convert your civvy vehicle to LED and no need to change voltage.

Or just make a set of 24V LED tow lights.

Or just run without lights from the storage lot to the lake. (Elephant Butte?)

 

[Lantzj22]

Convert your civvy vehicle to LED and no need to change voltage.

Or just make a set of 24V LED tow lights.

Or just run without lights from the storage lot to the lake. (Elephant Butte?)

Yessir, good old EB.
I thought about that but I’m more worried about if I hookup to other people’s going through town on a holiday weekend and the staters get me.

 

[M813rc]

As 98G said, for your own trailers, get a set of omni-volt LED lights, they usually work on anything from 6v to 36v.
If you are going to haul someone else's trailer, just swap in 24v bulbs. Or get a power converter.

You can easily make an adapter for the truck plug to civilian plug. The truck end has 12 wires, but you only need 4 of them if you are not going to run electric trailer brakes.
For my personal use, I made a military-to 4-way adapter using an old trailer cable spliced to a civilian plug. Reloader64 then made me a 4-way to 7-way adapter, so I can now light just about anything towed.

The diagram below should help. The military plugs have tiny letters next to each terminal.
Note that the colours listed are for the civilian end, and they may not be the same for all plugs (we found that out trying to fix Mkcoen's trailer lights one dark and stormy night!). For the military end wires, I just used a test light to identify which was which.

Hope that helps.

Cheers