M101A1, M101A2 Trailer Wiring

This post has little to do with the Jeep turbocharger project which has been on hold due to the cold weather. This is the wiring diagram for converting an M101A1 and M101A2 military trailer to civilian lights, at least it was for mine. I make no hard fast guarantees but this is what was inside my trailers.

Chart gives you the wires in three places:

Pin Numbers - The pin numbers refer to the actual Nato plug. The rubber plug will pop out with a little soapy water lube.

Wire Color - Color inside the plug in case you want to splice on the big civilian plug like I did. Colors could be very faded, use good light.

Tag Numbers - The tag numbers are the numbers on the aluminum tags where the plug harness connects to the trailer harness. If you simply wanted to tap into the trailer harness, the tag numbers will tell you which wires are which. Not sure if it is universal on all trailers but it was on my two and they are 8 years apart and made by different companies. My older trailer was missing a tag from a wire but connect the rest and you can figure it out.

Pin A - Convoy light (one of the blackout lights)
Pin B - Left Turn (wire is Red with a White Stripe) Tag# 22 461
Pin C - Convoy light
Pin D - Ground (wire is Black with a Red stripe) No tag number - ground lug
Pin E - Tail (running) Lights (Wire is Red) Tag# 21 489
Pin F - Spare
Pin G - Not Used
Pin H - Convoy Light
Pin I - Missing (both trailers)
Pin J - Right Turn (wire is Black with White stripe) Tag# 22 460
Pin K - Aux Feed (I put 12v to this) Tag# 37
Pin L - Not Used
Pin M - Left Turn (no it is not, no wire to this pin inside my plug)
Pin N - Right Turn (no it is not, no wire to this pin inside my plug)

Again not sure if all trailers are the same but mine are so I bet yours are too. Follow the link below to my video showing the wiring process.

Video Link:
Trailer Wiring