Temperature sensitive charging issue??

lwarrior1016 · May 21, 2022

Stangswagalicious said:
Ok guys heres the update. I never looked up a green wire tutorial, but i assumed it was just cutting the wire and hooking it up to a ignition on hot circuit. Well, i did just that and now every fuse under the hood stays hot weather the key is on or not. Wtf did i just do?

All i did was cut the wire by the pigtail close to the fuse box, covered the end of the wire attached to the pig tail, extended the wire goi g to the alternator and hooked it up to a fuse. Even if the wire is un plugged from the fuse box everything stays on. It killed the battery over night. Alternator works at least but thats no good if the car dies over night...

Can you post pictures of what you did and how the wires are ran on the alternator?

What fuse did you pull power from and how did you confirm all the fuses are staying hot?

I’m just trying to get as much info as possible.

Stangswagalicious · Jun 9, 2022

Friends, i have located the problem. The green wire was in fact not getting proper voltage. I spliced it into a wire thats only hot with the ignition on and it now works properly. Also for what its worth, the fuse box under the hood is supposed to be hot all the time. I do appreciate everyones help tho

I do not know why the green wire wasnt getting proper voltage. And tbh, i didnt feel like investigating it. I would be curious to know of probable causes tho. I hear the gauge cluster can have something to do with it?

95opal · Jun 9, 2022

Stangswagalicious said:
Friends, i have located the problem. The green wire was in fact not getting proper voltage. I spliced it into a wire thats only hot with the ignition on and it now works properly. Also for what its worth, the fuse box under the hood is supposed to be hot all the time. I do appreciate everyones help tho

I do not know why the green wire wasnt getting proper voltage. And tbh, i didnt feel like investigating it. I would be curious to know of probable causes tho. I hear the gauge cluster can have something to do with it?

Could have been something as simple as a blown charge light bulb or some other needle in a haystack hunt for were the wire was cut or damaged.

cobrajeff96 · Jun 9, 2022

Blown resistor, I'm thinking. There should be a 400 or 500 ohm resistor connected in parallel if memory is correct. Could've got cooked or something.

And I have another theory. Maybe it's slightly hair-brained but it's a shot in the dark.

I'm basing this theory off of what I already know to be true because I saw it happen many years ago in the searing Italian summer heat: copper.

Copper expands very easily in the heat and I would repeatedly see copper contacts in high-amperage circuit breakers trip every single summer I was there. Quite possibly, the field current connection on the back of the alternator's rectifier plate got severed at some point by some means, and the only thing that reconnects it is the expansion of the copper plate back onto that wire connection. Maybe, maybe not.

Stangswagalicious · Jun 14, 2022

95opal said:
Could have been something as simple as a blown charge light bulb or some other needle in a haystack hunt for were the wire was cut or damaged.

My guess is along the lines of what your saying. From some research iv done, that green wire runs to or through the gauge cluster. Something to do with the charge light. I could of replaced the gauge cluster, but what i did was free. So screw it. I just cant understand how it would only work when its warm outside??? Oh well. For anyone with a similar issue CHECK THE FIELD WIRE BEFORE YOU REPLACE 3 ALTERNATORS. lol

Stangswagalicious · Jun 14, 2022

cobrajeff96 said:
Blown resistor, I'm thinking. There should be a 400 or 500 ohm resistor connected in parallel if memory is correct. Could've got cooked or something.

And I have another theory. Maybe it's slightly hair-brained but it's a shot in the dark.

I'm basing this theory off of what I already know to be true because I saw it happen many years ago in the searing Italian summer heat: copper.

Copper expands very easily in the heat and I would repeatedly see copper contacts in high-amperage circuit breakers trip every single summer I was there. Quite possibly, the field current connection on the back of the alternator's rectifier plate got severed at some point by some means, and the only thing that reconnects it is the expansion of the copper plate back onto that wire connection. Maybe, maybe not.

Something about this simply has to be the case. Id think a blown resistor is going to cause it to never work. But who knows. The good news is, weeks of snoopin around and researching i fi ally found a fix!!

cobrajeff96 · Jun 15, 2022

Yea, so not a loss.

The batt light resistor might just be highly visible on the back side of the gauge cluster though. Could be an easy fix if that's it. And taking apart an alternator is actually no big deal. I wasn't sure what I was in for, but quite recently I had to. Here's just how simple it is...

I think it was only three screws or nuts to remove the vented back shell, and there everything was visible for me. The yellow wire is the Stator hookup. Check the inside of your alt next time you have a few hours to spare.

But first I'd say pop the gauge cluster off and check the back of it. It's only like a thirty minute job start to finish.