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72 coupe electrical problem

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Old Nov 9, 2022 | 08:22 PM
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Default 72 coupe electrical problem

I have been working on my coupe getting ready to replace carpeting, seats, basically complete interior. I had taken everything out, and.I mean everything. So my complete harness is there and want to test all my gauges and lights before I reassemble it. But I have no power to anything when I turn on the ignition switch. What did I mess up?
And now my ignition key will not release or go to the lock mode. This is a 4 speed, not automatic. I know I can remove the steering wheel and remove the ignition assy but thought someone may have a better solution.
As always, any and all help would be greatly appreciated.
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Old Nov 9, 2022 | 08:33 PM
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Make sure the lever on the column that would be moved by the reverse (manual) or park (automatic) is all the way up to let the key turn to the off position an remove





For the electrical, there's a ton of grounds in the system as well as common power points (like the horn relay) when you say it's out, are all of these connected?
M
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Old Nov 9, 2022 | 09:03 PM
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Yes sir, Thanks. Will check the reverse lever tomorrow. Nothing has been removed accept the engine was removed , gone through and put back in the car. zit is not hooked up yet, just the motor. I assume they connected the starter but haven't tried anything since the motor parts have not been put back together yet.
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Old Nov 9, 2022 | 09:11 PM
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Main power from the battery goes to the starter lug and then from there up everywhere else so if the starter is missing then not much will work
The Larger #2 wire from the battery must be hooked to the #12 red which would be on the same lug of the starter
M



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Old Nov 9, 2022 | 10:33 PM
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So I just need to connect the starter (pos & neg) cable back to the starter. What about the purple and fuse link?
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Old Nov 9, 2022 | 10:45 PM
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You should just need to connect the large black main + battery cable that is coming out of the transmission tunnel to the red starter wire that has the same size eyelet on it. That's the only connection from the battery positive to the rest of the harness. They are the ones that would go to the main post at the top shown here



The other purple wire is only needed for the starter and there's a smaller "yellow" (that's probably a red) that you don't need either, those are for the starter to work

There is also a smaller black wire with a larger eyelet on it that is in that same harness coming down the firewall... That's a ground wire that goes to the transmission bolt, NOT to this starter stuff at all, DO NOT CONNECT THAT TO THE STARTER MAIN LUG
M
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Old Nov 11, 2022 | 09:49 AM
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Had to move the reverse lever by hand, didn't move at all putting it in reverse. But it worked and got they out. Have to figure out why it isn't working.

You should just need to connect the large black main + battery cable that is coming out of the transmission tunnel to the red starter wire that has the same size eyelet on it. Lost me on this one, probably reading it wrong but reads like connecting + & - wires together. I do have a yellow on the left terminal, and a black (I think) on the small right terminal. Main large pos ( or is that the neg)) cable to the large center top post. Is that right?
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Old Nov 11, 2022 | 10:24 AM
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The large 2gauge black wire is from the battery positive terminal so it's actually a positive they just didn't use red wire for it.
ignore the two smaller side post wires, they are for the starter and to feed to the coil.
You should have a red wire that has a larger ring terminal that fits that center post of the starter, same size ring as the one on the large 2 gauge wire from the battery

M
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Old Nov 11, 2022 | 10:38 AM
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Originally Posted by Mooser
There is also a smaller black wire with a larger eyelet on it that is in that same harness coming down the firewall... That's a ground wire that goes to the transmission bolt, NOT to this starter stuff at all, DO NOT CONNECT THAT TO THE STARTER MAIN LUG
M
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Old Nov 11, 2022 | 12:18 PM
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OK thanks, really appreciate that info
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