M38 12V wiring

TNjeeper · Post by **TNjeeper** » Tue Jul 14, 2015 4:50 pm

Hello all, I just recently acquired a 52 M38 and am trying to bring it back to life. The electrical had already been converted to 12V when I bought it. I would like to put the original switches for the lights, ignition, and turn signal switch back in to keep the jeep visually correct. Can the 24V switches be used in 12V (with modification to the harness)? Or does anyone make these same switches in 12V?

Post by **wesk** » Wed Jul 15, 2015 12:05 am

Short answer is yes all but the turn signal.

The M38 never left Willys with a turn signal switch. The military turn signal kits installed in the field are getting expensive.

The military turn signals are 24 V but can be converted to 12 V.

It would take many paragraphs of explanation & details to walk you through installing the military main light switch and ignition switch in a civilianized system. Especially since we have no idea what has been done to your harness at this point.

Your best bet is to bury yourself in the excellent service manual wiring diagrams and sort it out.

If you must have turn signals just buy a modern Signalstat 12V kit.

Look at my many sub-albums for copies of wiring diagrams, pinouts and conversions. http://www.willysmjeeps.com/v2/modules. ... _album.php

4x4M38 · Post by **4x4M38** » Wed Jul 15, 2015 5:17 am

Wes,
There appear to be two military turn signal kits that I've seen for sale.

Is there a short treatise on converting one or the other and if
so, which is easier? Were both used on the 38's and A1's if used
at all?

Also, does one of the kits contains a basic Signal Stat switch?
I thought I saw one for sale a while back that was silver or chrome
but the instructions said to paint OD if in combat theatre.

Thanks,
Brian

Bretto · Post by **Bretto** » Wed Jul 15, 2015 5:30 am

I have all the look of the original gear but running 12V. I do not how ever have a turn signal stat unit. I built a signaling circuit out of relays and a flasher to run the rear brake/turn lights then just mounted a hidden 3-way switch under the dash next to my steering tube to control it.

4x4M38 · Post by **4x4M38** » Wed Jul 15, 2015 7:22 am

And you have a really nice wiring diagram showing same!

Post by **wesk** » Wed Jul 15, 2015 7:51 am

Yes there are many, many, many threads on this topic right here. Just push the google search button.

During my 22 years on active duty I saw all the choices and there was no rhyme or reason. Early military, late military and Signal Stat 24 V commercial.

My photo album is full of info on this. The military published how to service bulletins along with the kits. Over on Steel Soldiers a guy has a complete guide to converting the early military kit by using modern electrics to replace the 6 relay system.

Personally I see no sane reason to beat one's self to death trying to convert an expensive, hard to find military 24V kit to fit a jeep which is clearly a mildly civilianized jeep and not a trailered show queen. The military used all three so why not just buy the 24V civilian commercial switch kit and follow the simple directions in the kit just like the average motor pool guy did 40 years ago.