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Electrical issues? NOW WITH PICTURES AND INFO

northeastmoparnet

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What would cause my front light wiring to melt in a matter of seconds? Right down to bare wires for about 2 feet from the headlight and also the side marker light? Key was in the on position. Car would not start in the start position only making a buz at the starter relay. I removed the front harness and bought a new one, b ut do not think I should install the new one until I sort this out? How do I proceed to test this issue?

OK folks who have been following this thread. I have been trying hard to solve this issue. I checked and replaced my starter with a new mini starter. I replaced my starter solenoid switch. I checked all the connections and made sure they were all clean and tight. It was then mentioned on here to check my negative battery cable. I checked it as stated and everything looked fine. Now I know way up front looking for help I also said that electrical was not my strong area. I also had one or two fellow members tell me to change my negative battery cable. I do not want anyone to ever think I am not listening. And I did order a brand new made in the USA correct negative battery cable as I had on this car since it was totally restored in 2007. Car has always been in a heated garage and never out in the weather. Only took it for Sunday drives and car shows. I did receive the new negative cable today. Installed it in place and to my surprise, the new mini starter jumped to life. I could not believe that the cable was the problem. Because I had my steering wheel apart, I was assuming it was something I did, but again, I am pretty by the book guy. So my next step was to take the old cable and cut away the area in which I feel the problem was actually located. The battery lug where the two ground wires were molded into the end. I am now attaching pictures for good info and really wanted to know WHY? Looking at the cutaway you can see that these wires were twisted into 7 little bunches. They then appear to be just packed together and inserted into the lead terminal and then probably pressed in by machine. If you look at the smaller ground wire that attaches to the radiator/body support, you will also see it is twisted and also inerted into it's hole and crimped. So there also seems to be almost like a solder coating some of wraps and not all of them the same?? Which presents a question. I don't think these individual wraps would have been soldered and I think the solder you see on those wires is actually melted away from the battery lug due to corrosion and lots of resistance heat. So I am now concluding that when I tried to start my car, the power because of an incomplete circuit was trying hard to complete the circuit at the battery lug and could not get there, but it seeked a source of ground which was the other two small headlight ground wires that also go to and under the same fastener on the radiator support as the one coming off the battery lug. So those beacame the path of least resistance rather than being able to get back to the negative side of the battery, just followed the wires right to the end and melted those two headlight ground wires. Now, my question so I can really understand what took place is this? Were those 7 individual twisted sets soldered before the cable was built at the factory, or is the silver you see just the lead melted into them due to high resistance at this point which sent the power down the thinner ground wires as opposed to back to the battery right there at that junction. In the end, I would never have thought this cable would fail so badly and am just posting this for all to read and try and understand what happened. And I have to thank the members who told me to change that cable. You were correct, by now I want to know how and why so that in the future others can undersatand this as well. Thanks to all who helped.

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Dead short to ground. It should of burned up the fuseable link first. I would of found the cause before removing the harness.
 
Dead short to ground. It should of burned up the fuseable link first. I would of found the cause before removing the harness.
I still have the harness and can just plug it back in. I was originally thinking of taping up the bare wires and trying it again or testing?
 
I still have the harness and can just plug it back in. I was originally thinking of taping up the bare wires and trying it again or testing?
I see you are not to electrical savvy. You would need to examine the car and the harness. A short to ground burns back from the grounded area to the power supply.
 
I see you are not to electrical savvy. You would need to examine the car and the harness. A short to ground burns back from the grounded area to the power supply.
Not the best at electrical. However, This started with the car starter not engaging in the start mode. So I removed the original starter and bought a high torques mini starter as I have done on other cars. When I installed the mini starter it too, did nothing. I replaceds the starter relay which was giving me a buzzing and still nothing. During this try, I left the key in the on position, got out of the car and was standing by the fender looking at the starter relay area, and all of a sudden I got smoke billowing out from under the fender where the headlights on the drivers side are. I immediately shut the key off and the smoke stopped. So I was thinking there was a short in that harness and I unplugged it at the bulkhead and pulled it to unwrap the outer tape to look for a short. While I did not find any issues, I did find the black ground wire completely melted off the copper for about 2 feet down from the headlight connector and also the side marker light connector. I have since removed the started and had both starters checked and they both came back fine? I do not want to install the new M&H front light harness as this will possibly do the same thing. So I am thinking I should wrap the bare wires and install the harness. I still need to check the neutral safety switch area, the brake proportioning valve wire, and there appears to be some corrosion in the bulkhead where the bic #10 wire passes through, but it really does not look melted. Just needs a cleaning. So I am trying to figure out where to begin looking. Do those headlights and side marker lights have to be plugged in to replicate, or can I just leave the plugs hanging and check it? I will also be looking at the fuse box to see if I have all the fuses up and running? I will also say that I changed the ignition key cylinder in the steering column but I think the only wires that I moved there were the directionsl cam and the horn? Could one of those wires be gioing to ground? They are pretty simple plug and play, but who knows at this point?
 
Not the best at electrical. However, This started with the car starter not engaging in the start mode. So I removed the original starter and bought a high torques mini starter as I have done on other cars. When I installed the mini starter it too, did nothing. I replaceds the starter relay which was giving me a buzzing and still nothing. During this try, I left the key in the on position, got out of the car and was standing by the fender looking at the starter relay area, and all of a sudden I got smoke billowing out from under the fender where the headlights on the drivers side are. I immediately shut the key off and the smoke stopped. So I was thinking there was a short in that harness and I unplugged it at the bulkhead and pulled it to unwrap the outer tape to look for a short. While I did not find any issues, I did find the black ground wire completely melted off the copper for about 2 feet down from the headlight connector and also the side marker light connector. I have since removed the started and had both starters checked and they both came back fine? I do not want to install the new M&H front light harness as this will possibly do the same thing. So I am thinking I should wrap the bare wires and install the harness. I still need to check the neutral safety switch area, the brake proportioning valve wire, and there appears to be some corrosion in the bulkhead where the bic #10 wire passes through, but it really does not look melted. Just needs a cleaning. So I am trying to figure out where to begin looking. Do those headlights and side marker lights have to be plugged in to replicate, or can I just leave the plugs hanging and check it? I will also be looking at the fuse box to see if I have all the fuses up and running? I will also say that I changed the ignition key cylinder in the steering column but I think the only wires that I moved there were the directionsl cam and the horn? Could one of those wires be gioing to ground? They are pretty simple plug and play, but who knows at this point?
Headlights have nothing to do with the starter circuit. However if you have a bad or poorly connected battery cable that could be an issue. Up front was the body ground melted into the harness? Reason I say that is a poor battery to engine ground the starter when trying to operate will try to get a ground and can burn up any other body or chassis grounds. Do you have pictures?
 
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Headlights have nothing to do with the starter circuit. However if you have a bad or poorly connected battery cable that could be an issue. Up front was the body ground melted into the harness? Reason I say that is a poor battery to engine ground the starter wen trying to operate will try to get a ground and can burn up any other body or chassis grounds. Do you have pictures?
Battery cable is NOS and is in excellent shape. Ground from Battery cable to front of block is perfect. Ground from front light harness to radfiator support is perfect. No paint between and tight as a bulls ***. So I don't think those grounds have anything to do with it? This car was totally restored many years ago and never leaves my heated garage. Very puzzling.
 
Didn’t mention the negative battery cable to core support wire, is that in place?
My negative (black) battery cable has the thick black which goes to the front of the head on the block. It also has a small ground which goes to the radiator support next to the battery. All are in excellent shape and have no paint clean and tight connections.
 
Headlights have nothing to do with the starter circuit. However if you have a bad or poorly connected battery cable that could be an issue. Up front was the body ground melted into the harness? Reason I say that is a poor battery to engine ground the starter wen trying to operate will try to get a ground and can burn up any other body or chassis grounds. Do you have pictures?
OK, I taped all the previous bare melted ground wire and put the harness back in the car. Just left any headlight connectors dangling. Then I installed the new mopar high torque mini starter. Turned the key to just the on position and waited a few minutes and everything seemed to be ok. Then I tried to start the car and all I got was clicking from the starter.. I tried doing this about 4 times straight and all of a sudden, same wires I taped started getting hot and melting tape. So I shut it and disconnected the brand new battry I bought. I think next I am going to unplug the alternator and try it to see if there may be a short in my alternator. While doing that, I am also taking my steering coulumn apart to see if I jambed a wire when I installed the new key tumbler. This is very frustrating indeed.
 
My bet is on a bad negative battery cable, high resistance in one of the ends/terminations. Do a voltage drop test between the engine block and the negative battery post while attempting to crank. Leave the ignition switch off, jump the starter relay for testing. Nothing in the forward lighting harness related to key-on with any kind of current potential that could burn wires. Has to be the lighting ground wires in the harness trying to provide a return path from the starter to the battery. Too, get some jumper cables and jump the negative battery post to the engine block as a test.
 
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My bet is on a bad negative battery cable, high resistance in one of the ends/terminations. Do a voltage drop test between the engine block and the negative battery post while attempting to crank. Leave the ignition switch off, jump the starter relay for testing. Nothing in the forward lighting harness related to key-on with any kind of current potential that could burn wires. Has to be the lighting ground wires in the harness trying to provide a return path from the starter to the battery. Too, get some jumper cables and jump the negative battery post to the engine block as a test.
Thats what I told him in post 6. He says its all ok which it obviously is not. He needs someone that knows electrical a little better to assist him.
 
You need to measure the resistance through your ground cables, you can't just assume they are good because they look it. I have had a brand new battery cable that was junk because of a bad factory crimp. Looked fine, but it wasn't.....
Like stated above, my money is on a bad main ground cable. The starter is trying to pull its ground from somewhere else, but no other wires in the car are big enough for that current draw.
 
Once nice thing about '69 and back, in stock form... that can't happen. 70 and up has the extra small ground wire from battery to body and you bet your *** that starter will fry everything in it's path looking for ground if you have a bad main cable to the engine.
 
Once nice thing about '69 and back, in stock form... that can't happen. 70 and up has the extra small ground wire from battery to body and you bet your *** that starter will fry everything in it's path looking for ground if you have a bad main cable to the engine.
He said its perfect. One needs to define perfect.
 
I’ve heard there have been many problems with the more recent cheap reproductions of the original 2983778 (’70 and up) negative cable, poor crimps, high resistance. Never had a problem an OE version of that cable. While verifying the part number, found notes from 2009 where I paid a local dealer $14 for that original replacement cable, still available through Chrysler parts then. I see NOS 2983778 cables now at $160 and up.
 
With all these things frying and failing, it reminds me of my 1964 MGB that I owned many years ago. I needed a new battery and afterwards nothing worked and I fried the wiring harness. Afterwards, I discovered that the car was positive ground. I’m not saying that the battery is hooked up backwards, but melting the ground wire says something.
 
Thats what I told him in post 6. He says its all ok which it obviously is not. He needs someone that knows electrical a little better to assist him.
221Did I mention that I had the steering column apart to change the ignition key cylinder? I see that the large #10 wire is part of that bundle at the ignition switch. What if that big red wire hits the outer housing of the column when I try and crank the car? Wont that send power to the column which is grounded, not allow the starter to turn and also burn up ground wires?? I am going to dismantle the wheel and column and recheck my work in there.
 
221Did I mention that I had the steering column apart to change the ignition key cylinder? I see that the large #10 wire is part of that bundle at the ignition switch. What if that big red wire hits the outer housing of the column when I try and crank the car? Wont that send power to the column which is grounded, not allow the starter to turn and also burn up ground wires?? I am going to dismantle the wheel and column and recheck my work in there.
A dead short on J1-12R at the steering column would take out the fusible link before burning any wires by design. Again, leave the key off, disconnect the primary leads from the starter relay and jump the Batt and Sol terminals at the starter relay, crank or no-crank? You need to verify the high current starter motor circuit and cables are intact before chasing down all these other low current relay control circuits.
 
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A dead short on J1-12R at the steering column would take out the fusible link before burning any wires by design. Again, leave the key off, disconnect the primary leads from the starter relay and jump the Batt and Sol terminals at the starter relay, crank or no-crank? You need to verify the high current starter motor circuit and cables are intact before chasing down all these other low current relay control circuits.
The fusable link looks fine. No melting or heat which is also a strange thing? How do I check that fusable link?
 
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