Update on Dead Trailer receptacle

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Rick C
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Update on Dead Trailer receptacle

Post by Rick C »

If you recall, I was troubleshooting a non-working trailer receptacle. I pulled the harness down so I could see it better and removed the wrap back to the first junction. Seems all the double connectors that are exposed are labled 24....seems odd and I only get poer at one of them.....
I assume one or 2 are brake lights...which I didn't bother to test. My thinking is that the harness is bad. Got it in the late 90s from MVPC. At this point I think I'm going to try finding a new rear harness and just switching it out. Any ideas before I try dragging harnesses by the gas tank????
Rick
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Re: Update on Dead Trailer receptacle

Post by MSeriesRebuild »

Rick C wrote:If you recall, I was troubleshooting a non-working trailer receptacle. I pulled the harness down so I could see it better and removed the wrap back to the first junction. Seems all the double connectors that are exposed are labled 24....seems odd and I only get poer at one of them.....
I assume one or 2 are brake lights...which I didn't bother to test. My thinking is that the harness is bad. Got it in the late 90s from MVPC. At this point I think I'm going to try finding a new rear harness and just switching it out. Any ideas before I try dragging harnesses by the gas tank????
Rick
Was your present harness a NOS one when it was installed? At any rate you will need to get a new reproduction harness from someone like Joe Hall at Vintage Wiring of Maine. NOS just can't be trusted, too old & deteriorated right out of the box.
Charles Talbert
www.mseriesrebuild.com
knattrass
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Post by knattrass »

Hi Rick - 24 is the b/o taillamp and there is a double conn upfront that splits it (20 to the front/24 to the rear). 24 then runs back to a molded 3 way splice (on ours) that then runs to left/right/trailer. Sounds like that 3 way might be an issue. 22 is brakes with 460 right rear turn and 461 left rear turn. We bought a set of Sid's harness to replace everything but ended up making our own rear harness because we were using the 4-wire Humvee taillamps. We moved some of the splits upfront inside the cab near the glovebox to keep them out of the elements. We also pulled parallel wires versus attempting all the splices - so we have a dedicated wire to the right rear and a parallel wire to the left rear, etc.

We did not have the heart to chop up Sid's rear harness and it is sitting in a box in the basement. Its all douglas connectors - let me know if you want it - we paid something like $65 or close to it.
Rick C
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Post by Rick C »

Thanks guys. I'm just confused because all the douglas double connectors on the rear cross member are labled 24 and only one has power when I have the BO lights on. The harness was a repro from MVPC. Everything works great except the trailer receptacle. I wouldn't care except I have a really sweet M101 that I'd like to tow legally......
Rick C
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Post by MSeriesRebuild »

Rick C wrote:Thanks guys. I'm just confused because all the douglas double connectors on the rear cross member are labled 24 and only one has power when I have the BO lights on. The harness was a repro from MVPC. Everything works great except the trailer receptacle. I wouldn't care except I have a really sweet M101 that I'd like to tow legally......
Rick C
We have had some reproduction harness # labels that were wrong in the past. It would pay you to get a diagram & double check things.
Charles Talbert
www.mseriesrebuild.com
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