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2004 Civic LX undiagnosable power issues

Looking for a little advice regarding some issues I’ve been happening. The first incident happened about a month ago, while I was driving. My car slowly lost some electrical abilities, radio, lights, heat, and even the electrical odometer turned off. Shortly after the engine turned off. When I pulled over and checked it out I was getting no power to anything whatsoever. All signs point to alternator failure. Had it towed to a shop, and had an inspection done. Only for them to tell me that they charged it up, because the battery was completely dead, let it idle for an hour, and kept testing the battery, but nothing happened. It was charging exactly as it should, and no issues could be found. So I paid them, drove it home and it worked perfectly fine, even when using the electrics to the max. At this point I just assume it was the weather. I live in Iowa and that was a -32° morning. 2 weeks later the exact same thing happened again. Only this time I didn’t tow it, I just got a jump and limped home. But yet again, once it sat a little bit, it started up and charged just fine, producing 14+V while idling. A few more weeks go by, where I check the voltage before and after I start it, every time getting 12 before, and 14 at idle. suddenly, a few days ago I’m only getting 10V at idle. That persisted a couple days, so I didn’t drive it. Then finally today I have a day off work, I’ve got an appointment for an inspection, then I go out to start it and now I’m getting 14.5V. This problem never stays around long enough to figure out what it is for sure, and I really don’t want to just throw parts at my car if it doesn’t need them. So here’s hoping that given the history of the issue someone here can give me some advice. Thank you.

How old is the battery?

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It’s an interstate battery that I just got about a year ago

With a 15 year old car there are plenty of possible places for loose/corroded connections in the charging system, possible corroded cables, than kind of thing. I’d have all those checked, then I’d have a good mechanic check out the alternator and battery again. If everything besides the alternator is good, my guess is the alternator has an intermittent open somewhere.

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The problem might be caused by a faulty ELD.

http://www.gonzostoolbox.com/KnowledgeFolder/HondaELD.html

Tester

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