ThatXJGuy
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- Riverton, Wy
So I am in the process of getting my M-55 road ready for the first time in over 20 years, and am trying to get all the lights in running order. I have a few questions and would also love some opinions and input from what others have done.
First off, i'll start with the questions: how many wires are SUPPOSED to be running towards the rear of the truck? In TM9-8028 page 282 is a diagram of the electrical system, however not included in that diagram are the turn signals, or what the rest of the wires on the trailer receptacle are supposed to be. Why are there 12 prongs on the trailer plug and what are they all used for? My truck has 5 wires, of which only 3 are required for the lights, 4 if you have backup lights, or I guess the other two are probably blackout system wires.
I am currently trying to figure out what previous owners/operators/mechanics have done with the system and trying to get it mostly back to stock. I got to the point that I got the turn signals to come on (just solid, no blinking) and got tail-lights, but when I went to get brake lights working, someone had cut the wires to the brake switch and left them there, and the switch was stuck closed even when you weren't on the brakes. I pulled the switch apart and fixed that, and then realized that the brake system needs to run through the turn signal system in order to have both systems run on one filament in the rear bulbs, and the switch needs to have separate outputs to the fronts and rears so that the brake doesn't light up the front turn signals. At this point I pulled apart the turn signal switch in order to figure out how it worked and just became more confused... How do the rest of the older 5 tons work? I am dealing with most of the harness that has been cut apart and wads of electrical tape and snap lock connectors everywhere and just a real mess. Since this truck hasn't been used in 20 years, I am also having a slightly difficult time telling between the 20 year old electrical tape, and the 52 year old tape and of course whatever happened in-between.
I am pretty close to just yanking it all out and starting over, and I am considering switching the lighting system over to 12V which would be relatively easy, but it gets slightly more complicated if you want to do it in such a way that the batteries stay even. I ended up buying a new turn signal switch that can be used in either 12 or 24V systems (with a switch of the indicator bulb) 12V and 24V relays and flashers, but can't quite decide which way to move forward, based on a huge amount of confusion on how the original system is supposed to be, and wanting to keep as much of the functionality of the truck original, but wanting to have a fully modern-comparable system meaning front and rear, left and right turn signals, 4 way flashers, and of course brake lights. Backup lights would be cool too since my rear fixtures have a white area that would otherwise be wasted, but they may or may not be my permanent fixtures. My original taillights were missing when I got the truck so I am free for anything back there, and I am missing a lens on the front left light so I may end up replacing those as well. The inside of that fixture has pretty well rusted out to top it all.
Anyway, thanks in advance! I think there is a pretty good lack of electrical threads going these days so a good conversation on the topic wouldn't hurt I don't think.
First off, i'll start with the questions: how many wires are SUPPOSED to be running towards the rear of the truck? In TM9-8028 page 282 is a diagram of the electrical system, however not included in that diagram are the turn signals, or what the rest of the wires on the trailer receptacle are supposed to be. Why are there 12 prongs on the trailer plug and what are they all used for? My truck has 5 wires, of which only 3 are required for the lights, 4 if you have backup lights, or I guess the other two are probably blackout system wires.
I am currently trying to figure out what previous owners/operators/mechanics have done with the system and trying to get it mostly back to stock. I got to the point that I got the turn signals to come on (just solid, no blinking) and got tail-lights, but when I went to get brake lights working, someone had cut the wires to the brake switch and left them there, and the switch was stuck closed even when you weren't on the brakes. I pulled the switch apart and fixed that, and then realized that the brake system needs to run through the turn signal system in order to have both systems run on one filament in the rear bulbs, and the switch needs to have separate outputs to the fronts and rears so that the brake doesn't light up the front turn signals. At this point I pulled apart the turn signal switch in order to figure out how it worked and just became more confused... How do the rest of the older 5 tons work? I am dealing with most of the harness that has been cut apart and wads of electrical tape and snap lock connectors everywhere and just a real mess. Since this truck hasn't been used in 20 years, I am also having a slightly difficult time telling between the 20 year old electrical tape, and the 52 year old tape and of course whatever happened in-between.
I am pretty close to just yanking it all out and starting over, and I am considering switching the lighting system over to 12V which would be relatively easy, but it gets slightly more complicated if you want to do it in such a way that the batteries stay even. I ended up buying a new turn signal switch that can be used in either 12 or 24V systems (with a switch of the indicator bulb) 12V and 24V relays and flashers, but can't quite decide which way to move forward, based on a huge amount of confusion on how the original system is supposed to be, and wanting to keep as much of the functionality of the truck original, but wanting to have a fully modern-comparable system meaning front and rear, left and right turn signals, 4 way flashers, and of course brake lights. Backup lights would be cool too since my rear fixtures have a white area that would otherwise be wasted, but they may or may not be my permanent fixtures. My original taillights were missing when I got the truck so I am free for anything back there, and I am missing a lens on the front left light so I may end up replacing those as well. The inside of that fixture has pretty well rusted out to top it all.
Anyway, thanks in advance! I think there is a pretty good lack of electrical threads going these days so a good conversation on the topic wouldn't hurt I don't think.