Multiple alternators not charging
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Multiple alternators not charging
Hey all. 1999 F-350 powestroke 4x4 sngle alternator setup. Battery light came on this weekend, found alternator was putting out zero volts at the B+ terminal. Replaced with remanufactured NAPA and I was getting 3V at the B+ terminal on the alternator with the large battery lead disconnected but the 2 wire connector in place. Decided maybe a bad remanufactured so I exchanged for s new NAPA, same thing, tried a remanufactured motocraft, same thing. From what I understand these are internally regulated and I have 12V at both the smaller green and orange wire in the 2 pin connector. From what I understand is those wires power the alternator and as it runs I should have 13.-15 volts coming off the large B+ terminal on the back but I'm still getting around 3. NAPA dud say they're having a bad batch of replacement alternators but I would suspect after 3 replacements there's something else up. Any secrets? Tried clearing codes with SNAP on solus between alternators, still nothing.
Fleet Owner
Joined: Apr 2008
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If he's telling you that there's a bad batch I would buy one from someone else. I once went through 4 starters from the same place. I got tired of changing them so I returned it and bought one elsewhere and never had another issue. However with that being said, even if the alternator isn't putting out, you should have battery voltage at the B+ terminal unless the 2 fusible links are blown.
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Yes battery wire disconnected, still putting out about 3 volts. Cleaned and tightened ground and verified continuity to ground from alt case to battery negative, but just to be sure used a jumper cable to give alternator direct path to battery negative and still getting 3 volts
FTE Leadership Emeritus
Joined: Sep 2000
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From: Stephensville WI
If he's telling you that there's a bad batch I would buy one from someone else. I once went through 4 starters from the same place. I got tired of changing them so I returned it and bought one elsewhere and never had another issue. However with that being said, even if the alternator isn't putting out, you should have battery voltage at the B+ terminal unless the 2 fusible links are blown.
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Get about 3 volts. Had alt tested at napa and o'Reilly that passed it. Called a friend who's a service writer for ford and the tech told her to check the fuse links, but I'm getting power at the executor wires when running
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Cross-Country
Joined: Jun 2016
Posts: 91
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From: Parker, CO
Running an alternator without a battery attached is a great way to quickly blow up an alternator & the rest of your electrical system. Without the battery there to dampen voltage fluctuations you can get WAY more voltage than you should into your electrical system & fry things.
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