M1102 - Wiring Problems

I am in the process of converting my 1102 trailer over to 12v. I am following the post below and i have everthing working except for the running lights. When i hook the brown wire from the 4 wires coming off of the truck to the solid red wire I get no running lights al all. Even the running light on the truck go off. When the trailer plug is disconnected, the running lights on the truck work fine. I tried to connect the brown wire up to all the other remain wires and i get nothing. I have not replace the 24v running lights with the 12v number 96 bulbs yet. as far as i know, they should work on the 24v bulbs, but will be dim.

Any ideas?

If you have a military pigtail coming off your trailer, here are the color codes that correspond to the wire circut numbers. The wire colors are the indiviual wires that are INSIDE the outer black rubber insulation.

24-484
22-461 LEFT TURN/BRAKE RED WITH WHITE TRACER
24-483
21 MARKER LIGHTS. RED
23
90 GROUND BLACK WITH RED TRACER
22-460 RIGHT TURN/BRAKE BLACK
37

This may help you .
Civy truck to MIL trailer wiring info

Why dont you just put new bulbs in and buy the plug adapter off ebay instead of hacking up the wiring???

ryan77 said:

Why dont you just put new bulbs in and buy the plug adapter off ebay instead of hacking up the wiring???

Click to expand...

Or get some multi-volt surplus LED's and use it either 12v or 24v .

Porky, can a person use multi volt LEDS in any of the M series trailers? If so, what would the bulb number be that would be used?

RetiredNavy said:

Porky, can a person use multi volt LEDS in any of the M series trailers? If so, what would the bulb number be that would be used?

Click to expand...

http://www.truck-lite.com/webapp/wcs...4204&langId=-1

i agree, i should have just gotten the adapter and lelf the mil plug in place. But, i dident. i cut it off and replaced with a standard civ 4 wire setup.

Again, everything works except the marker lights. when i connect the red wire from the trailer as mentioned in the article to the brown wire from the truck, the marker lights on the truck go off, and i have no marker lights on the trailer either.

any ideas?

Check the ground if you wired it as diagramed it should work.
The trailer is aluminum. steel is a better ground.

There is a short somewhere.

i agree, there is a short someplace......but the question is, how do you find it?

Welcome to the fun world of electrical gremlin troubleshooting..

Did the lights work before you cut the wiring harness ?

Cutting the harness was a bad idea, as all the wires are tagged with metal marker bands as to what they are. time to break out the multimeter and start tracing wires. Where exactly did you cut the harness? take a pic and post it, all hope may not be lost.


There are only 4 wires you need. All the others, forget about, as they are BO lights.


Civilian trailer wiring

Green wire = Right turn/stop light
Yellow wire = Left turn/stop light
Brown wire = Tail/marker/running lights
White wire = Ground




Military harness circut # and Pin
22-460 Pin J = Right turn/stop light
22-461 Pin B = Left turn/stop light
21 Pin E = Tail/marker lights
90 Pin D = Ground

http://www.ltw.net/Hummer/074424.pdf PDF page 196, TM page 5-4 Thats the diagram you need.

Where exactly did you make the cut? I think I know what you did, but need to confirm. Did you hack off the 12 pin plug leaving the thick cable?

yes, i cut off the 12 pin plug leaving the thick cable. i stripped the outer casing off to expose the red and black wires. are color coded and i followed the information below.

UPDATED INFO:


If you have a military pigtail coming off your trailer, here are the color codes that correspond to the wire circut numbers. The wire colors are the indiviual wires that are INSIDE the outer black rubber insulation.

24-484
22-461 LEFT TURN/BRAKE RED WITH WHITE TRACER
24-483
21 MARKER LIGHTS. RED
23
90 GROUND BLACK WITH RED TRACER
22-460 RIGHT TURN/BRAKE BLACK
37

Check all the wire bands where the thick cable connects to the body hareness. Make sure all the #'s match.

ok, i will check that in the morning. I'm asuming you are talking about under the trailer where the junction box is? i was looking at that this afternoon and it looked correct but, i will checj again.

Yes, under the trailer. Match the tags tag to tag. Make sure they are tight.

Check your PM's. Give me a call if you want.

On your TRUCK, do you have a flat blade 7 wire, or a 6 pin round wire connection??