Trailer receptacle

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Rick C
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Trailer receptacle

Post by Rick C »

Tried towing my M101 today, no tail lights. Can't get power from any plug at the receptacle but all the lights work on the M37. Any idea? Tried grounding plug but no change.....
Rick C
Lifer
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Post by Lifer »

Get yourself a continuity tester...either a light or an ohm meter...and test each hole in the socket for current flow. If there is none, you have an "open" somewhere. Could be a loose connection, a corroded connection, a disconnected wire, or a broken wire.

Make absolutely sure you have a good, clean, solid ground before you start testing, though. If you don't, testing the individual circuits won't do any good.

Once everything is okay on the truck, check each of the circuits on the trailer for the conditions described above and make extra sure that each light is well grounded to the trailer chassis and that the ground wire to the plug has a good, clean, solid connection at each end.

Have a cup/can/bottle of your favorite beverage at hand while you work and you'll enjoy the task. It sometimes takes a long time to isolate the problem, but electricals are really easy to diagnose and repair.
"PER ARDUA AD ITER"
Rick C
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Post by Rick C »

LOL Lifer, already had the beverage handy whenever I do anything electrical. Tried a ground wire right to battery, nothing at the receptacle.....in any of the plugs. Is it possible there is a problem in the double connectors under the tailgate hinge? Its annoying because all the lights in the truck work fine, just nothing at the receptacle, not even the blackout lights. Have you ever disassembled that receptacle?
Rick C
Lifer
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Post by Lifer »

I haven't torn into that (yet). From the sound of things, everything is normal until you get to the connector for the receptacle. You might want to have another sip of your beverage and then take the connector apart. Clean everything up good, check the condition of all wires and connections from there to the receptacle, fix anything that looks "iffy," and put it all back together. You should then have power where it needs to be...at the receptacle. If so, have another sip of your beverage and pat yourself on the back for a job well done. If not, have two or three more sips of your beverage and let us know what happened. We'll try to help you sort it out. :)
"PER ARDUA AD ITER"
knattrass
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Post by knattrass »

Rick - There are the 2 double connectors up under the gate, both are splits for the respective turn signals. The service light double is up under the hood on the right splash shield side. The rest I can't remember without my drawing. We still have the harness laid out on the basement floor if there are any other questions.

We took apart our trailer recepticle. You'll need some silicone spray - careful your hand doesn't get slippery and you drop your beverage thou. If you take a blunt punch the size of the terminal, you can push the wiring pin out of the recepticle with care - spray, push, sip... spray, push, sip... take your time.

Its hard to believe that everything went bad across all those different pins. Park the trailer next to the truck and run a ground and jumper wire from the 24v batt and touch each pin on the trailer terminal to see if they all work if you have trailer questions.
Rick C
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Post by Rick C »

As far as I know, all the underhood connections are to connect front/rear harnesses. Again, all the tail lights work. I did disconnect the double connector under tailgate hinge that was marked 24 which should be blackout markers. Had power at one pin there but nothing at the receptacle. I'm thinking I have to pull the plug apart and see what is going on there.
Rick C
Lifer
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Post by Lifer »

Make sure your beverage supply is well stocked! ;)
"PER ARDUA AD ITER"
refit1701
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Post by refit1701 »

You just need a double beverage holder helmet, painted OD and a chin strap...
-John
Member of Dixie Division MVC

1953 USAF M37 wow, restored
1962 M151 Ford Production, on the rotisserie now
1953 USMC M37 w/w -in storage
1942 M6 Bomb Service Truck (sold to UK collector)
1967 M116A1 Pioneer Trailer
1968 M101A1 Trailer
S-89 Comm box
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