This is my first post here, I would like to say hello to everyone. I have a 91 5speed manual 3.0 V6 Runner. Lately I have a problem; before I start the car the battery voltage is about 12 volts, and when I start it instead of being 14 it is still at 12. I really doubt that it is the alternator because of the symptoms. To begin with the brake light and the battery light in the dash go on and off simultaneously. When I start the car the voltage is at 12, and both the battery and the brake lights are on. Once I rev the engine to about 2000 RPM both of the lights go off, but the voltage stays 12. They lights will occasionally flicker on and off. This is the main reason why I believe this problem to be electrical and not mechanical. The car starts without a problem so its not the distributor or the started.

If anyone know anything that would be a great help, I can't drive until I get this fixed because my battery will die. Is it possible that it is a short somewhere in the alternator and brake light wire? Are they located in the same place?

Thanks in advance for your help.

 

I think its your alt. you can test it by starting your car and put a screwdriver near the center of the alt. pully and if it has a magnetic charge to it (it pulls the screwdriver in toward the pully like a magnet) then your alt. is creating a charge and it should be charging the battery, if its not pulling the screwdriver then its not charging and u need a new alt.

 

http://www.4x4wire.com/toyota/mainte...nator_brushes/

 

Wow, thanks for your input, both of you, I hope you are wrong, but I fear you are right.

 

That tells you it IS the alternator. !