1988 Chevy Astro charging

Did you do any testing, before you replaced anything?

You can place voltmeter leads across battery posts, with everything turned off, take a reading. Start the vehicle, take a second reading across the battery posts, the second reading should be higher than the first, if the alternator is charging. You can also take a reading at the bat terminal on the alternator.

If you think there is an access drain, with everything turned off, you can check amp draw, around 30 ma.030, should be max. You could also try a testlite between the battery post and cable, it shouldn't lit-up, but it's best to check the amp draw. You can check there are no interior lites left on, in the vehicle, glove box, overhead interior lite, under the hood, in the trunk. You can also pull fuses one at a time, when you pull the correct fuse, no more drain.

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