It started when my alt. light would flicker at low rpm and then I would rev and it would go off. After a couple days like that the car finally died on my way home. So I jumped the battery and the car started right up and I drove it home. When I started the car the alt. light would be on. I had the battery checked and Checker said it was ok. (I’m not fully trusting they’re advice) So I pull the alternator out and have it tested, 14.4 V so it’s was ok. I put everything back together and thought maybe a lose belt. So I tighten the belt to spec and the alt. light goes out upon starting. Problem fixed right. wrong.
Now when I’m driving the interior lights start to dim(clock, etc.) and when I stop for awhile the thing won’t start. Not getting enough juice. So I jump again and it starts right up and does the same thing again after awhile of driving or sitting over night. Note: while driving and the lights dim the alt. light is not on at all.
So either the battery is not holding charge, the alt. is not completely bad but going out or what? Or the regulator is bad in the alt.? Thanks for the help guys.
Thanks man, I kind of knew it was. Just an FIY, it’s not good to unplug the battery while the car is running. Search, there’s plenty of info on it. L8ter
its perfectly fine to do so, i’ve tested alts on over a dozen cars just like that and never had a single problem. some over 30 years old, some as new as 03… for a quick test that will prove what your problem is it works well. i’ve looked at some of the reasons people try posting and honestly there retarded, energy is energy plain and simple, and a battery is not a filter. there is no danger to your ECU or any other vital part of your electrical system. you can do more damage with a shorted ground or power wire then that
i’ve seen certified techs do so occasionally as well. unless you have a $50K+ car and like throwing money at problems that are just ghosts, its not really an issue.
Not to start any shit but if you have seen any certified techs do it they were either old or really fucking stupid, and alternator takes voltage to make voltage, if you disconnect the battery you automatically full field the alt and it usually destroys the diode pack. Try searching on the web generators are what you would use that old school method on, but hey what do i know im only a “certified tech” with more than 12 years of experiance under my belt
like i said, i’ve never had any problems with it, none of my friends have, no one i’ve suggested it to has, etc
the only problems i hear with it seem to be from the web with little to no support behind the claims.
btw i was being sarcastic up top, im not trying to start shit either, all i said was i’ve never had, or even known anyone that’s had a problem from useing that method to test there alt
You may not have had a problem with it but its not an accurate test of an alternators output strength. I’m not saying i have heard of problems when this is done im saying i know this will cause problems when this is done. If you have done it before with no recorse than that is great but mark my words IT WILL bite you in the ass one day. If you want to test your alternator use a meter and figure out how to field your alternator with a voltage source still applied, this will be an accurate reading of an alternators total charging potential. This test is best when tested back to back against no load and full load. Your almost correct in your thinking about the battery not being a filter but is more like a shock absorber for the system in that it smooths out bumps and dips in the amp flow, without that absorber there you are more likely to do damage to other components, maybe not right that second, but damage will occur