Testing a starter with a Power Probe is one of my most fundamental skills as a mobile mechanic. This short article will explain the process and give you a couple tips from my personal experience that make the process easier and faster.
If you’re trying to do this test, you already suspect that you have a problem with your starter. This could be either that the starter clicks once when you try to start the car, clicks multiple times, or doesn’t click at all. This test helps to rule out possible causes of starting problems by bypassing some parts. The ignition switch and cabling from the ignition switch to the starter will be bypassed during the test.
What is a Power Probe?
If you’re reading this article, you probably already know what a Power Probe is. For those who don’t, it’s a tool that connects to your battery. It allows you to send power to a circuit using a probe tip (it’s also capable of grounding a circuit). Here is what it looks like and it is widely available online or in physical stores.
You’re going to use your Power Probe to send power to the starter signal terminal. Designs vary on starters in regards to where the signal terminal or post is. In general, it will be the part where the smallest wire attaches to the back of the starter. I have circled the signal wire for this starter.
How to test your starter with the Power Probe
Simply place the tip of your Power Probe on the metal terminal and hit the “forward” button. At that point, the starter will either turn or it won’t. If the starter doesn’t turn, that often but not always means that the starter is bad. Stay tuned for another article discussing what the results of testing your starter with a Power Probe means.
Ways to make it easier
One way that I like to make this process easier is by attaching a testing lead to the starter signal terminal. Oftentimes, your Power Probe will be too long to fit in the space you have to reach the starter signal terminal. So rather than trying to work your tool into that space, just bring the signal terminal to you! You just clamp one end of the test lead to the starter signal terminal and the other to the tip of your Power Probe. These test leads are inexpensive enough that you can modify them, too, without worrying about messing them up. If the alligator clip tip isn’t right for your situation, try cutting it off and attaching a blade-type terminal, for instance.
If that sounds like a lot to get in to, you’re right! This work can be complicated and tiring. You may find yourself asking, “Is there a mobile mechanic near me that could help me with this?” If that’s the case, you can start an estimate or simply get in touch.