Connect it to a 12v source & read the output voltage on the other side. If it reads 6v it's good. I wouldn't hold it in my hand while testing it though. It bleeds off the current as heat.

Last edited by Tiny; 07/29/2014 9:35 PM.
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.