24v trailer wiring

maple_leaf_eh · #1 02-06-13, 04:57

I am considering a long distance roadtrip towing a civilian cargo trailer with my M151A2. It will be a one-way trip for the trailer, so I do not want to put a great deal of effort into the wiring and lights. I have a set of magnetic trailer lights that could be re-lamped to 24v. I have the SMP vehicle to trailer connector cable with a dozen individual shielded plugs. The lights are already working with a 4-wire system.

What does the collective wisdom suggest? Where can I find 24v lamps for commercial 12v sockets?

rob love · #2 02-06-13, 05:22

Assuming your magnetic base lights are using 1157 bulbs, then you would want to replace them with 1662 bulbs, which are the 24v equivalent. NAPA carries them for under $1 each. They are used in the dome light of the LSVW if I recall correctly.

From the military trailer plug, you will want to hook wire #90 to ground, #21 to the marker/running lamps, #22-460 to the right turn bulb and #22-461 to the left turn bulb. On the magnetic lights, usually the yellow is the left turn, and the green is the right turn. Remember that green is for the grassy side of the road and yellow is for the chicken side. The other two wires will likely be white (tail lights) and brown (ground).

maple_leaf_eh · #3 02-06-13, 18:22

OUTSTANDING! Thank you Rob, I will give it a try.

rob love · #4 03-06-13, 04:51

Always glad when all that redundant info floating around in my head can be of use to someone. Good luck.

Depending on the age of your trailer harness, it may or may not have the 22-460 and 22-461 wires marked. It may just say 22. The 22 will be the rear left (22-461) while the wire coming off pin J will be 22-461.

Harry Moon · #5 03-06-13, 19:20

Recently when ordering LED bulbs for my trailer I remember them being 12/24 volt bulbs. If you just switched to LED bulbs would that work?

rob love · #6 03-06-13, 20:21

The multi-voltage LEDs are becoming more and more common. They will not solve the trailer connection problem, but are ideal where you want to switch the trailers between SMP and commercial towing.

The Truck-lite SMP tail lights (the large plastic kind) are now available in 12-36 volt range, and are also perfect for a jeep trailer that occasionally gets towed behind the family pickup.