Battery Trouble Light

[AHall]

Hello,I have a 1993 240SX fastback with no mods that I have been driving since it was new. Yesterday I noticed that the battery light was dimly lit while driving. When I returned home, I checked the battery voltage and the battery seemed okay as the voltage was 12.7 volts. I then started the engine and checked the voltage at the battery and the voltage was unchanged. I then unplugged the harness connector at the alternator and the voltage was zero at both pins. Does this mean the alternator needs to be replaced? I replaced the original alternator in 1998 and was just thinking how I have not had a problem with the alternator since the original was replaced.

Any assistance would be appreciated.

[ricebike]

if your battery v stayed the same when started, you shoulda stopped right there

take out your alt to get it bench-tested, i believe your alt brushes are worn out... was that replacemen alt a used one or a rebuilt one?

[h.240]

I agree with ricebike. The voltage should be closer to 14.5 when the engine is running.

[AHall]

Thank you for the response. It was indeed the alternator. It has been replaced and the car is now running fine.

Again thank you for the help.