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2004 Honda Civic - 5 alternators

2004 Honda civic lx I have had some underlying electrical issue for years now the power fluctuates high and low I’ve replaced and rebuilt the alternator 4 times now in as many years and still have the issue I’ve been to 3 different mechanics and the newest guy swears up and down its not the pcm or other part that controls the voltage as he replaced that just to check it and the battery is fine I said so if we replaced it with a brand new one and it still happens then what he said maybe something with the wiring harness… I’m tired of having this issue and everyone just says it’s the alternator but I’ve already replaced that it’s not the pcm or other part there it just makes no sense please help!

What power fluctuates? Headlights, interior lights, everything? Do you have an alternator gage in dash?

No I do not and everything does the alternator spikes at 18 [Honda shouldn’t be over 15 I believe] then drops to almost nothing and just repeats so if i drive at night it looks like im flashing my lights and the mechanic is telling me he swears it’s the alternator but I’ve already had other mechanics replace that 4 times so it’s just hard to believe that’s the issue

There is an ELD electronic load detector in the fuse panel. They run around $50. I’m not so sure that it could override the voltage regulator to allow 18 volts into the system, but who knows. Could try that and if it doesn’t work, I’m betting faulty regulator in alternator.

He replaced that just to check and it didn’t fix the issue so he also said it’s the alternator but I’ve had brand new ones in there and still had the issue it just makes no sense honestly and the ol lady doesn’t want to replace the alternator a fifth time just to have the same issues… There must be something ruining the alternators to quickly then??? I usually get about a year out of them then it dies and I gotta replace it

Check or replace cables and wires to and from alternator.