Ok, a little background information:

I bought and installed an optima red top back in November or so because it was the stock battery, and was going on its 4th winter, so i figure It would be safe to buy a new one.

About a month ago, My battery light would start coming on for a few minutes and shutting off during normal driving, it went away for a while, and came back a few days ago solid. It would come on now only in slow traffic with a lot of accessories on, and go off when id turn the accessories off . Finally, it came on and stayed on for a full day when driving even with the accessories off.

So, I figured it was the alternator, since the battery was fairly new. I bought and installed a new one. The next day, ( yesterday) the battery light came on after about 10 miles of driving, and stays on constantly now. When I turn the car on, after 1 minute of it being on, the light comes on.

I checked the voltages of the battery and alternator when the car is on, and idleing(this is also with the battery light on), I get about 14.78V at the battery, and right around 14.8V at the output terminal of the alternator, so it can't be that either is bad that i believe. I havet driven it more than 25 miles with the new alt. on because I was afraid it would die, but now that I saw the voltages, I cant see how it could.

Is there something else I should be checking for or that it could be? Any help would be appreciated.

Hi ANDIX

If you try the link below it is a very interesting article on Alternators.

I just wonder if you have a CS121 or CS130D alternator in your car(My books and all the info are for 93 2.2's)

If you read through the article, which is interesting anyway you will find a paragraph which states that the CS121 or CS130D , in Normal operation--shuts down if it overtemps and then works normally when it has cooled down.

I am nor sure, of course, if this is your problem but if it isn't then you probably have a straight indication circuit fault as the Battery and Alternator outputs appear fine to me.

Hope this helps and let us all know how you fix it


Good luck


Alont


http://members.bellatlantic.net/res00d4r/alt_theory_rev/Alternator_Theory.html

I had the same EXACT problem you were. Its the reason I now have a red top in my car too. There are few things to check. Inspect the wire on the back of the alternator (make sure you get a good connection). Make sure that the plug-in thing is properly seated. Make sure your getting a good ground on the battery (maybe buy a 6ft piece of 4-8guage wire and some terminals and make yourself a "hyper-ground" kit).

In my case, the ground wire had some bad corrosion on it in a couple places and once I replaced it I didn't have any more battery light problems.

I kinda had the same problem today. I'm running a yellow top with a 4alterstart 180 amp alternator. Upgraded big 3, and hypergrounds. I got in the car, battery light was immediatly on. My volt gauge was stuck at 11.5 volts. This is about .5-.8 volts for what it really is. all accessories off, revved the engine a lil, stayed at 11.5. I drove the car for less than a minute, and the light went away, and my voltmeter went normal. Any ideas on that one?