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Battery intermittently going dead

My husband has a 99 Ford Ranger. It started intermittently loosing power and the battery would be completely dead. The battery showed to be bad so he replaced the battery. Car ran fine for 4 months. Then one morning he went to leave for work and it was dead again. Had that battery checked it showed to be bad replaced again and everything ran fine again until a few weeks ago.

Had alternator tested. It showed to be bad. Replaced alternator and serpentine belt. Took dead battery off and charged. Car started and ran fine for a day. Left for work this morning got 3 blocks. Everything went dim all dashboard lights came. Battery level went to 0 and car died.

Need thoughts and suggestions on where to go from here.

Have a shop check for parasitic drain. Check both ends of the battery cables for corrosion.

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Get the battery charged and confirm that the alternator is working then remove fuse #26 from the dash mounted fuse box every time you shut off the engine and if that eliminates the battery discharging you’re in for some serious diagnosis but that’s the starting place.

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Yep… Parasitic drain; happened to me once, turned out to be turn signal flasher.

That is a charging system failure, not a parasitic drain. He needs to diagnose the charging system failure.

Ask your shop to do this simple test. Make sure the battery is fully charged the day before, then let the car sit, unused, overnight. Before the first start of the next day the battery should measure about 12.6 volts. Then immediately after starting the engine, 13.5 - 15.5 volts. Report back what you shop measures. My guess is the first alternator was bad, and the subsequent replacement battery problems were caused by that. And you got unlucky, the replacement alternator is also bad, or there’s a belt or wiring system/fuse problem remaining. In any event the voltage test described above is where I’d start.

Maybe you left something disconnected. But from starting without a jump to having 0 volts after dying 3 blocks away is strange.

The way I read this is that an alternator fried 2 batteries… then it was in the process of frying a third…when the alternator was then replaced. At that point he had a good alternator (assuming new is good) and a battery that was likely partially fried from the former alternator which was likely overcharging.

So… now we have a good / new alternator and a damaged battery which was removed and charged…or attempted to be charged and re installed and assumed good.

We need yet another good battery…to bring everything up to snuff…as well as an alternator health check. Hopefully your new alternator is still functioning properly…and not destroyed by the damaged battery.

The entire scenario was basically what happens when something is misdiagnosed and replaced and everything is assumed to be good to go and yet it was not… .

Bad alt…fry’s batt… new bat…same alt… fry another batt… new alt…partially fries new batt… … Same Alternator on a suspect batt… Now Alt suspect as well as batt… imho.

Thats how I interpret the situation…