Battery Light Stays on

[jameson75]

Hello everyone:

I have a 1993 MR2 Turbo. The battery light stays on after the car starts. Since the car isn't driven often, I decided to change the battery. The alternator has also been changed before, maybe about 4 years ago. After changing the battery the light still stays on. I have this battery charger/tester machine. When I connect it to the battery its reading at about 13-14. The engine is on and I can see the volts moving up. when I put a load on it (turn the lights on, radio) it drops down to 12.9. when i turn the load off it moves back up to mid to high 13's volts. so i'm assuming the battery is being charged by the alternator?

Any ideas of what it can be??? BTW, my reverse lights don't work either, even after I changed the bulbs. do you guys think that might have something to do with the battery light?

thanks in advance.

[Hajoca]

Alternator has a regulator (diode pack) that seems to be malfunctioning.

[jameson75]

Thanks for the prompt reply. I replaced the alternator a few years ago and it wasnt a pleasant thing. Is the regulator a part on the alternator that i can replace or do i have to replace the entire alternator. the alternator is such a tough part to get to.

thanks.

[Hajoca]

There is a diy for alternator rebuild here on the forum by TERCELGTS ??
The alternator has to come out no matter what, you should be able to check by grounding the field windings, look at the camry service manual in the camry links section (same alternator).
Then if the voltage goes back up then your regulator is bad.