Alternator drains battery while driving or running

1995 FORD F-150

135,000 MILES • 6 CYL • 2WD • AUTOMATIC

BLANCO68

MEMBER
3 POSTS

It has a new battery and alternator a week old.
had one new alternator replaced a couple of days ago after having tested at AutoZone they said was bad so on second alternator while driving or running it starts running down battery terminals are not corroded or loose

Jan 21, 2022 at 2:31 AM

AL514

✓Experienced Mechanic
5,642 POSTS

Hello, there may be an issue with one of these fusible links, after a while they can get corroded inside but you won't see it. I would check these as well as the ground connections. Take them off and clean them really good so there's a good metal to metal connection. The fusible links you can check with a multimeter or just replace them. They work the same as a fuse, they burn up if there's too much current flow, but once they get corroded inside, they can cause all kinds of problems.
The grounds G119 and G117 and very important, they are the grounds that go to the engine block, so verify all the ground connections you can find, they will all eventfully lead back to the battery negative. And provide ground for the Alternator.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

https://www.2carpros.com/articles/how-to-use-a-voltmeter

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Jan 21, 2022 at 4:41 AM

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