I know how to test if the alternator is charging at the battery with a digital multimeter, but im not sure about how to test the voltage at the alternator directly, i have a haynes manual but it doesnt really explain where the multimeter lead goes. How do i do this? do i need to go from underneath the car? Also just to make sure, the alternator has 2 connections on it right? the sensor that you plug-in....and the ground connection right beside it that you have to screw on. Just confirming because i read a thread where someone said it has 3?


Heres a pic of the alternator, can someone can show me where to place the leads of the multimeter on it

http://www.theautochannel.com/autopa...9940945ylh.jpg

 

Put the positive probe on the B+ terminal of the alternator. That's the terminal with a cable running from it to the positive terminal of the battery. It has a rubber boot on it that you just pull up to get access to the terminal. Put the negative probe on the negative battery terminal. You don't need to be under the car.

No reason to do this unless you measure less than 14 volts at the battery with the engine running, and suspect a break or corrosion in the cable between the alt and the battery.