Topic: Could someone please send a pic of the harness/alt
in Forum: C3 Electrical
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Hello, could someone please send a pic of how the alternator wires are attached on an 81? Someone completely bached the wiring and used wire nuts to connect the wires but I know it's wrong because the battery is not charging and the volt gauge doesn't work. I do have a wiring diagram but if I could get a pic or two of the wires coming out of the harness and connecting to the alternator I would GREATLY appreciate it. Thanks very much in advance. George
malo68 2008-04-02 19:27:29
Woah, I just disconnected the wirenuts and switched two red wires to check if they had been crossed and now I get a reading of 17.10 volts on the alternator. The alternator had been replaced with a later model one. Is this normal? Can't be...
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This aint stock but it's correct. Do you have the plastic plug on the side? Maybe they put the single wire without the plug on it and wired it all up. And yeah 17 might be a bit much, 14+/-
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17v will fry some of the electronics, and the battery, if left like that too long.
A properly functioning alternator/regulator will put out around 15v MAX, and around 14.5 on average, when needed. Once the battery is fully charged, the alt should go down to around 13v avg.
The pics above show the correct wiring...
A properly functioning alternator/regulator will put out around 15v MAX, and around 14.5 on average, when needed. Once the battery is fully charged, the alt should go down to around 13v avg.
The pics above show the correct wiring...
Joel Adams
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Found and fixed the problem. Seems that it was showing 17v for just a second then set my tester into the negative reading. Apparently it was grounding out. The alternator thermo wire was fryed at the point where it goes through the firewall. It was like that before I got my hands on it, honest
I had to unbolt the harness retainer block bolt and the fuse block (fun) from the inside and I replaced the wire with a new one. Don't know what could have caused it to do that but it's good now, charging 14.10 v. Thanks for the advice all. Couldn't have done it without the electrical diagram. Thanks Joel! malo68 2008-04-04 21:05:44
I had to unbolt the harness retainer block bolt and the fuse block (fun) from the inside and I replaced the wire with a new one. Don't know what could have caused it to do that but it's good now, charging 14.10 v. Thanks for the advice all. Couldn't have done it without the electrical diagram. Thanks Joel! 
Another success story.
Congrats on solving the mystery.
On to the next problem.
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