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Alternator or something else?

2003 Chevy Venture with 125k. Two weeks ago, the battery light was coming on for a few minutes at startup and then going off and on sporadically. The shop said I needed a new battery. i was on the factory original and got a new one. Battery light went away for a few days but now it’s back, off and on sporadically, but now the ABS light comes on occassionally too, not as often as the battery light. Last night, we were driving home in the dark with the battery and ABS light on. The clock flashed very bright a few times and both warning lights went out. Took it in to the shop and now now they’re telling me I need a new alternator.

And a month ago, I needed to get a new intake manifold into it because it was all gunked up from Dexcool.

Does this sound like the alternator or something else? The ABS light has me worried.

Well, the ABS and battery/charging systems are two entirely different things. It is possible that you have some sort of electrical short somewhere that is doing random things with radios and warning lights. If you can think of anything that goes with odd light behavior (e.g. rain, bumpy roads, anything) then it might give you some clues.

Other than that you might just have 2 entirely different issues.

Auto parts chains and battery places will test your charging system for free if you want to double check that diagnosis.

I have an '00 Sihouette and have noticed that the electrical connectors for most everything are just cheap junk. I have had air bag lights, ABS/Trac Control lights, and power window issues that were all just about loose/dirty connectors. Maybe you should start my just cleaning up connectors.

Sounds like a loose or corroded connection.
Wiggling wires and connectors might force the issue.
Was the charging system tested?

I had a nissan frontier that died on the road. My battery light AND brake light came on at the same time. A few (50) yards later, the engine quit. That told me the alternator died because it could not charge the battery enough/quick to run the ABS or spark. Once the alternator died, soon the battery discharged and there I was. Stranded.

There is a link between alternator light and ABS light, not in the function of either but in the monitoring, I have changed only one Venture alternator, best to do it from below and lower the sub frame a little.

Will the test from the auto parts store show a bad alternator even if the battery light isn’t on when it’s tested?