coil wire grounded
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From: Finksburg Maryland
coil wire grounded
I had two wires on the + side of the coil. I took both of them off. It has a pink wire that goes over towards the starter. I think this goes to the starter solenoid. The other wire was black and goes through the firewall to under the dash. I'm reading a short to ground on that wire. Can anybody give me a location of where this wire goes? I'm trying to read the wiring shematic but the colors don't seem to be the same. Plus its a jungle of wires under there. Does anybody have any suggestions? Its a 72. Thanks
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From: Finksburg Maryland
I can't make heads or tails out of these diagrams. It looks like the wire I'm chasing is a black/pink wire that goes from the coil +, to a wiring block, and then turns pink and goes through something (don't know what the symbol is), then goes to the water temp gauge, fuel gauge and then to the door ajar light. I just want to make sure I'm not going to hurt anything if I start the car with it disconnected.
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From: Finksburg Maryland
I looked a little closer. The wire thats grounded out is the resistance wire that takes over once the car is running, so you have less voltage and don't burn the points up. I mainly need to know where this wire goes. Does it go to the fuse block, or ignition switch, or somewhere else? I assume that since it goes to the + on the coil, I shouldn't be reading continuity from the end of the wire to the valve cover. I need to locate where its grounding out.
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From: Finksburg Maryland
Obviously, I don't know what I'm doing.I'm not even sure if I'm on the right track. I'm just trying to figure out why the resistance wire that goes on the positive of the coil, seems to be grounded. When I turn the key on, I get 12.2 volts. If the wire was grounding out, I don't think I'd see 12 volts. I don't know.
Melting Slicks
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From: Piedmont Va
St. Jude Donor '11-'12-'13,'19-'20
Obviously, I don't know what I'm doing.I'm not even sure if I'm on the right track. I'm just trying to figure out why the resistance wire that goes on the positive of the coil, seems to be grounded. When I turn the key on, I get 12.2 volts. If the wire was grounding out, I don't think I'd see 12 volts. I don't know.
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
I don't have my wiring diagram handy, but there are two possible reasons why you are measuring a "short" to ground with the key off. As dosoctaves said, the switch might ground out when shut off. Or, the switch might just "open up" when the key is moved to off. There are probably several low resistance loads (to ground) tied to the same point on the ignition switch output, and these multiple, parallel, low resistance loads will look like one very, very small resistance ( a short) to the meter. (Just basic electronics with multiple resistors in parallel.)
Also, notice that you got 12.2 volts with your meter (the correct reading). DO NOT ever let someone tell you that the ballast resistance lowers the voltage to the coil. You have proved it does not.
Also, notice that you got 12.2 volts with your meter (the correct reading). DO NOT ever let someone tell you that the ballast resistance lowers the voltage to the coil. You have proved it does not.
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From: Finksburg Maryland
But I read a short to ground with the key in any position. Why would a positive wire read a short to ground? I put everything back together and tried to start it. It was starting before but backfiring badly. It turned over one time and then I smelled the wires burning. Done for the year. Maybe next year.
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
But I read a short to ground with the key in any position. Why would a positive wire read a short to ground? Assuming you disconnected the battery when you were doing the resistance tests, it can read a short to ground for the very reason I stated in my earlier post. It's a common electrical phenomenon. I put everything back together and tried to start it. It was starting before but backfiring badly. It turned over one time and then I smelled the wires burning. Done for the year. Maybe next year.
Melting Slicks
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From: Bay Area CA
The black w/pink lettering resistance wire goes to the main harness connector under the brake booster, it ends there, on the other side it is fed by a pink #12 normal wire that gets it's voltage from the ignition switch. There is a tie in to a blk/pink normal wire the acts as power to all the gauges, between the ignition switch and the main connector. The ignition switch is fed from 'Batt' on the fuse box-which is fed, unfused from the main + battery cable, by way of the main red power coupling at the horn relay, protected by a fusible link to the main + cable at the starter. It should be capable of delivering 40Amps w/o opening, and probably closer to 60. If you have a short in the wiring in this area, it will fry your wires before the fusible link opens. I will take an almost direct short to ground near the coupling to open the fusible link. A 16 gauge wire will carry 20 amps and fry. You need to find that short. The reason you most likely will measure a short to ground on the ign wire is because of the tap in on the gauges to power wire. with the ign off that side upstream is open, but the gauges + leads (wanting to be powered) sit there, and you are measuring through them to ground, all in Parallel. You need to find that short. C.
Team Owner
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From: Crossville TN
The 'reddish' wire comes from the "R" terminal on the starter solenoid, and is covered in yellow fiber jacket (hi-temp insulation). lt provides 12 volts to the coil when starting the engine. The resistance wire comes from the junction block, and it feeds the coil with lower voltage when the engine is running. Both these wires are connected to the positve (+) coil terminal. {Interestingly, my '71 wiring diagram shows them going to the negative terminal...but that is just wrong.} The wire coming off the distributor gets connected to the negative coil terminal.
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From: Finksburg Maryland
Well maybe I'll try again today. I'm assuming its the purple wire going to the starter thats burning. Nothing was burning when I had the key turned on. Just when I tried to crank the engine. I'm wondering if its possible for the starter solenoid to lock up and draw too much current. I'll see if the purple wire is grounded out. I guess this wire shouldn't show any continuity to ground. I'm not sure now.
Burning Brakes
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From: roanoke va
Well maybe I'll try again today. I'm assuming its the purple wire going to the starter thats burning. Nothing was burning when I had the key turned on. Just when I tried to crank the engine. I'm wondering if its possible for the starter solenoid to lock up and draw too much current. I'll see if the purple wire is grounded out. I guess this wire shouldn't show any continuity to ground. I'm not sure now.
In one of your post above you said it was reading grounded but it also checked 12 volts with the switch on. If this wire was grounded you would have blown a fuse,blown a fuseable link or smoked a wire.
You also said it was not wanting to start up a kicking back or something like that. That could be a timing issue.
What were you doing or what happened to be looking for a shorted ing. wire? I don't remember seeing a reason you wre looking for a short on this wire? Did you do something to the car an update a mod. or something else to maybe cause the problem you had before you started looking for a short?
A little more back ground to your problem may help out in fixing it.
Just a thought, Wilson
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From: Finksburg Maryland
Well in another post, I explained that I installed a new air filter, but it was hitting the base of the coil. I bent the coil back on more of a slant, so the air filter would fit. After I did that, the car was backfiring through the carb and mufflers and it was missing. I thought I may have damaged the coil so I put a new one on. It still wouldn't run so I put a new cap and rotor on, checked the points, new wires and still no good so I was trying to trouble shoot the coil wiring to see if there was a problem. I moved alot of wires under the dash to see where the resistance wire and such were going. The next time I tried to start it, it turned over one time and then I smelled the wires burning and everything went dead. Thats where I'm at right now.
Melting Slicks
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From: Aurora Ontario
Sounds to me like you need to find the burned wire(s). I was following your other thread. I think you may have loosened up something when you were fiddling under the dash. Can you get a good look up there? Try and see if two wires are melted together or if a wire has been pulled loose from something.
Jim
Jim
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From: Finksburg Maryland
From looking under the dash yesterday, before the burning wires, its going to be a nightmare. Everything on the car was working, but there are wires that are taped off, disconnected, and wrapped around everything. Looks like I'm going to have to pull everything apart and decipher where everything belongs. This should be fun.