charging porblem? 99 civic LX
 

Have been chasing what seems like a low-charging condition on mom's car. Had dead alt & battery (best charge voltage was 12.1v, was usually 11.65.). Replaced alternator, battery, & belts. Now, volatge jumps to 14.2v right after engine start, stays there for up to 30 seconds, and then drops to 12.68v, and stays there. I finally found a wiring diagram for the alt (no real troubleshooting chart, though). What info it had said that the PGM-FI 'oversees' the voltage regulator to improve fuel ecomony (damn silly Honda!). Battery never dies, no charge light on, everything works ok (headights are a little dim at idle until car is driven 30 minutes or so, then get better.) Now, can anyone tell me if this is normal, or provide me w/ some tips to figure this one out (factory troubleshooting chart, maybe?) Much appreciate.

Re: charging porblem? 99 civic LX (cuppie1975)
 

Honda Charging System Overview and Diagnosis

You need a muliti-meter in order to use the above info.

Re: charging porblem? 99 civic LX (EE_Chris)
 

Thanks for the link. I'll check that out next week, as soon as the car gets out of the body shop (minor incident w/ a Liberty!)

Re: charging porblem? 99 civic LX (cuppie1975)
 

One last question on this (for now): What is the minimum system voltage w/ the engine running? That's the only piece missing from the link you gave me. Help is much appreciated (and yes, I do have a good meter, and even a hald-held scope.)

Re: charging porblem? 99 civic LX (cuppie1975)
 

i have a horrid charging problem myself.

basically the battery is not getting charged if its not getting like 13.6 or more volts,
or something in that range.

so if your at 12v or less, then basically your just running off battery power,
like i am.

everything might work ok,
but after a few weeks the battery will die,
and it wont come back untill you replace it, or just take it to an autoparts store and have them manually charge it up for u(takes about 40min).

i'm working on mine at the moment again.
you can see my massive post here.. https://honda-tech.com/zerothread?id=937098