This might sound stupid but I don't have much experience in testing electrical connectors/switches/relays, etc. I know I've seen people using a small black box with a red and black wire that measures conductivity between two points (to make sure a current is passing through) that reads a number in the display and other ones that make a beep and read a number. I've also seen those test light things that look like a screwdriver with a small bulb in the handle that lights up. I was just wondering if someone could explain the diff. between these, and how to generally use them, which one is best, that kind of stuff. I know it may sound trivial but like I said, I have no experience with electrical testing and I'd like to learn. thanks in advance.

 

The digital multi meter (DMM) is the best way to test your circuits. A test light only shows if you have power in a circuit whereas the DMM tells you how much voltage, etc is in the circuit. If you use a test light that is not computer safe, you could cause damage to sensitive circuits.

 

Go to sears.com You can buy a book to show you how to use one.