barrman : Trailer Plug

Trailer Plug
Post by barrman on Aug 24, 2006, 1:32pm

My quest for the last few weeks has been stock wiring. Most of my stock wires are still on the truck. The fire department just ran wires next to them, added switches and cut off the ends of the stock stuff when something didn't work. I now have all the pieces needed to go back to all stock wiring for the the lighting system. My students have made a bench top "mini" lighting system over the last week or so. We figured out that my 3 lever switch is bad, but only on the blackout lights circuits. It will do until I get another one. I have 4 students each sanding on a different light bucket as I type this. I hope to paint them this weekend and put the guts back in. Another student is working with a hammer to straighten out the frame ends that hold the rear light buckets. This will let me return the rear of the truck to completely stock lights and wires. Except for the trailer plug.

I have all my trailers set up for the round 6 pin civilian trailer plug. My M715 has this on it as well. Is the 12 pin military plug specific to only military uses or does it have a civilian equivalent?

I saw a military trailer pig tail on e-bay the other day. I didn't see any recepticles. Anybody have both that they want to get rid of?

Re: Trailer Plug
Post by tacomainoh on Aug 24, 2006, 4:06pm

what goes bad in a 3lever switch???

Re: Trailer Plug
Post by 40grit on Aug 24, 2006, 4:15pm

if you can pull the 3 lever apart, I'd clean up the contacts inside...I'd guess you got some "crud" on the BO terminals


maybe even just cycle it a whole bunch of times, it may self-clean...

Re: Trailer Plug
Post by brute4c on Aug 24, 2006, 4:30pm

Depends...some have a plastic interior that cracks/breaks internal parts....the unlock lever can fall out of its place and short the switch....wire connections, solder points, internal resistor....I know theres more...

Re: Trailer Plug
Post by tacomainoh on Aug 24, 2006, 4:40pm

so simple, obvious stuff that should be fixable? schweet.

Re: Trailer Plug
Post by brute4c on Aug 24, 2006, 4:45pm

The ones with the plastic guts have a seal that basically you have to break to get into the switch...and then if the plastic parts are the failure point, not sure that they can be gotten seperately....they suck...I had one and I dissected it and posted pics some time back, now lost, of the cheapo interior...within 2 months of getting it, the headlights wouldnt always come on....the plastic cam was slowly bending inside and not letting the contacts touch....

Re: Trailer Plug
Post by fisherman on Aug 24, 2006, 11:56pm

By receptacle you mean the plug on our trucks the trailer plugs into? I have one of those I probably won't be using that you could have.

Re: Trailer Plug
Post by barrman on Aug 25, 2006, 8:52am

Tacoma,
Here is what I am getting on the bench top with the current switch:

TOP LEVER
"Stop Light" does not give power to either brake switch lead but, does allow the blinker system to work.

"Service Drive" give me head lights and tail lights like it is supposed to but no dash lights no matter where I turn that other lever.

"BO Marker" Transfers no power anywhere except to the dash lights.

"BO Drive" is the same as BO MARKER

The "lock" lever just turns. It doesn't lock anything.

Aux SWITCH

Turning this one to Park gives me running lights at all 4 corners and allows the blinkers to work.

As long as the Main switch is on one of the BO settings, the "Panel Brt or Dim" works like it is supposed to.

That is how it worked on Tuesday. Now, the "Park" setting has to be hunted for and I can hear an arc inside the unit if I play too much. Obviously, the switch is bad.

I have left my "bench" setup intact until I can get a picture of it. That will happen when my students leave in about 20 minutes. Then I will try to take the switch apart and my next group of students are going to cut a hole in the dash to the left of the steering column for the switch to mount.

Fisherman, PM coming.

Re: Trailer Plug
Post by brute4c on Aug 25, 2006, 10:55am

The unlock lever, lower right of the 3 lever light switch, is there to keep the top lever from moving when one doesnt want it to. Basically the top lever, on the inside of the 3 lever housing, has several teeth....the unlock lever is connected to a strip of metal that fits into one of those teeth...when the unlock lever is lifted, it pulls the metal strip, which is connected to the far opposite edge of the unlock lever, down...thus pulling the opposite edge of the metal strip out of whichever toothed recess in the top lever it is in. Then the top lever can be moved to whatever position and the unlock lever released, thus putting the metal strip into one of the other toothed positions on the top lever....

A pic would be so much easier....I wish I could draw....

Anyway, if one repeatedly moves the top lever without lifting the unlock lever, the chance is much higher that the metal strip on the unlock lever will become disconnected from the unlock lever and then you have a long metal strip moving around freely inside of the unit with metal connections, some live, all over the place...for those who have had a switch that shorts out and you hear the loud click of the internal circuit breaker, then you hit the switch and things reset after a bit, this is why.

So, in a properly working switch, the unlock lever does do something...one can test to see if the unlock lever is working properly by attempting to move the top switch with the unlock lever lifted and without...if it is much harder to move when the unlock lever is not lifted...perfect...if it makes little or no difference, it could be a problem soon...if not already. I wouldnt recommend doing this very often though....

I know that wasnt your problem Tim...just sharing the little seed knowledge that I do have....

Re: Trailer Plug
Post by brute4c on Aug 25, 2006, 10:58am

Hmmm...maybe it is part of your problem....you can take them apart from the rear....just be very careful not to dislocate all those little metal pieces in the front part of the unit....

I have to wonder about your unlock levers metal strip being loose due to your "I can hear an arc inside the unit" comment...