How to Diagnose a Blown Fuse in Your Car

Video Transcript

"Hi, my name is Nate McCullough on behalf of Expert Village. In these clips we're going to talk about the proper way to diagnose and replace your vehicle's fog lights or accessory lights. In this clip I'm going to start with the very first thing you want to check if you have a fog light failure. The most common failure for your vehicle's fog lights is going to be a blown fuse. What I have here are two fuses, they're both 15 amperes. I'm going to hold this one up here; this is a good fuse. As you can see in the middle of it, between the two electrodes that touching my thumb, there is a piece of metal. That piece of metal has been engineered to burn out at a specific amperage rate. And this you can see this one is not burnt out. I'm going to show you one that is burnt out. I'll hold this one up here. If you look in the middle at the horseshoe shape piece of wire, you can see that it's burned, discolored, and the connection has been broken between the two electrodes that are touching my thumb. This is the bad fuse. If you notice that on your fog lights, that is going to be your problem. I'm going to pick up my fuse box cover, this particular vehicle happens to have two of them. I will show you them here. Some vehicles have a separate fuse for your fog lights. Some vehicles do not. If it does not, that means that it's going to be wired into one of the various other electrical systems, possibly your headlights or your ignition circuitry. If everything else works on your vehicle, and you do not see a specific fog light fuse listed, that means the fuse is not your problem just due to deductive reasoning that means that it's not going to be the issue. This is another fuse box, this goes to the power distribution center under the hood. We're going to take a look for our fog light listing. If we don't see it, that's going to indicate that our fog lights are wired into another circuit and as long as everything else on the vehicle is operating correctly, then you know that your fuse is not the problem."