M101A2 12V lights!? What am I doing wrong?

[TRACTION]

I'm trying to convert my M101A2 to 12V and a 7 pin adapter but for the life of me it just isn't working like it appears it should.

Here's where I'm at:

Replaced all the bulbs with 12V versions
Purchased a 7 pin pigtail
Downloaded a user manual for the M101A2 to identify what wires are what.
Removed military pigtail.
Connected the wires according to this chart:

Pigtail wire - Function - Trailer wire
Brown Right/Left Tail Light 21
Green Right Turn Signal 22-460
Yellow Left Turn Signal 22-461
White Ground

When connected this way the lights don't behave as expected.

Right signal blinks both parking and right tail light
Left signal lights right tail light
Running lights only activates right tail light.

I'm confused. Is there a trick to this that I'm not aware of? The concept is simple but I think I'm missing something.

Any help is appreciated.

Mark

 

[TacoDell]

are you sure your ground is good ?

I'd double check that... and make sure you have good metal to metal contact on the ground.

 

[TRACTION]

I'll double check the ground. I attached it to the original ground location with an existing bolt but will grind away some of the paint to make sure.

 

[LandCruiserPhil]

Verify these results again
Right signal blinks both parking and right tail light
Left signal lights right tail light
Electrically they dont make sense

 

[elcoyote]

If you wired in the 7 pin socket to your vehicle on your own without a kit and you have amber turn signals, you will require a taillight converter like this: http://www.hopkinstowingsolutions.c...ndard_converters/tail_light_converter_60.html

If you have red turn signals on your tow vehicle then you may have a bad ground or a ground fault.

 

[Borrego60]

Double check your ground wires,I had the same problem with my m416.

 

[Bella PSD]

I had the same problem with my M101A3. Nothing was working right. All wires were installed correct according to the M101A3 user manual. Had 12V lights and good ground.

I took the M101A3 AND M101A2 trailer lights apart to see whats going on and the military light is full of circuit boards. I think that might be the problem. At least on mine.

I had no problem with my M416 lights and from the outside they look the same as the M101A3 lights. Had no problem with my Military pioneer tool trailer lights either, just wire them up and install 12V lights.

 

[TRACTION]

I ground down the paint for the ground to no effect. Absolutely right it doesn't make sense electrically. I verified all the connections per the manual and the diagram for a 7 pin pig tail and the lighting pattern is still wacky.

I was able to shift around the connections to get the tail lights to work by connecting BRN to 22-460 connector and the right turn light by connecting GRN to 21 but none of the remaining connectors work for Left turn signal (Yellow) so something is not right here.

Long term I need to ditch these lights anyways since I plan to convert to the trailer to a dump bed so what I might just do is replace them entirely. Any suggestions for a replacement light that'll be relatively secure for offroad use? There really isn't much frame material to work with at the rear and with the drop tailgate I can't really mount lights in it.

If I replace the lights I'll probably rip out the whole wiring harness and start from scratch. I just wanted to get the lights working so I could get a few loads of bark before the winter sets in.

 

[Borrego60]

That sounds like a better plan.

 

[TRACTION]

Think I figured it out. The 7 pin pigtail doesn't match the diagram I have for wire color and function. Used a continuity tester to verify and it's all different than what I was expecting. Haven't rewired the trailer yet but I'll be this'll fix it. Should have done this first but didn't know that the wire colors weren't standard among various manufacturers.

Beforehand I pulled the lights themselves and they test correct and there is no circuitry in these versions thankfully.

 

[Bella PSD]

If you don't have the military lights with circuitry in them then you should be fine. I really think that circuitry was the only problem I had. I'll check back and see how it turns out. Good luck and some pictures of your new trailer....

 

[TRACTION]

Yep that was it, rewired the setup with the correct color wires and viola it works. :wings:

Once I start refinishing the trailer I'll start posting pics on a project thread.

 

[Hill Bill E.]

Should have done this first but didn't know that the wire colors weren't standard among various manufacturers.

Beforehand I pulled the lights themselves and they test correct and there is no circuitry in these versions thankfully.

I found that out the hard way also:Wow1:

Another thing to watch for on old Military trailers, since all the wires are black (and tagged with metal bands w/#'s) some of the Military 'mechanics' would just cut and splice under the trailer, to get the result they wanted, regardless of the wire numbers.

If that's the case, having the original schematic is useless.

 

[nat]

If you don't have the military lights with circuitry in them then you should be fine. I really think that circuitry was the only problem I had. I'll check back and see how it turns out. Good luck and some pictures of your new trailer....

My lights still have the circuitry in them and they act odd when the headlights are on.

I guess the best thing is to strip the LED stuff out and just leave the regular bulb sockets?

 

[Antichrist]

Long term I need to ditch these lights anyways since I plan to convert to the trailer to a dump bed

You mean a different dump bed than the current configuration that dumps?