Time for a tool review. Its time because just used it tonight on the Bronco, I used it yesterday on a semi trailer, the day before on a combine, you get the idea, I use it alot.
Its called the Power Probe. I have the Probe III, and I think I bought it about 10 years ago. It might look like a bit of test light, but let me tell you, its so much more.

The Power Probe can not only be used like a test light, but it can also be used to energize circuits, test components like relays, switches or bulbs. It does require 12v to operate which you can either get from a cigarette plug or straight from the battery. The Probe III kit comes with a extension cord also, this makes it long enough to test a light bulb at the back of a semi trailer from the truck batteries. On the face of it there is a rocker switch that you can either energize a positive or negative circuit. Close to the probe end there is a lead with a with a clip that is a ground, you can use this to test a motor or a bulb.
Here’s a scenario for you. Lets say your window washer stopped working. First, you check the fluid and then the fuse, but still not working. Now, with the Power Probe, you can connect to the plug going to the pump and see if the power is making it there. Then, if it is, you can energize the pump and verify if it actually works or not, its just that easy.
They sell all over, Napa, Snap-on, Amazon and much more. The Probe III costs around $119. There are several other models, here is a chart to help you find the one that best suites your needs.

So please, I beg of you, if you work on your own stuff or for other folks, buy one, you wont regret it. This blog post is not paid for by anyone, I bought my Probe III for full retail off the Snap-on truck, I just think everyone needs one. This weekend I will do some demos on our Youtube and post a link here. Now, go fix something!