How to Check and Replace Automotive Fuses

Having electrical components that aren't working on your car can be irritating. Still, it doesn't have to mean an expensive trip to the repair shop!

In most cases, you can change a blown-out or failed automotive fuse yourself, for no more than the cost of the part – and however long it takes you to replace it!

Checking car fuses

Checking the fuses is the most technical part of this task, and even that’s easy to do!

If you notice one electrical component not working on your car, check everything else before you start looking at fuses. If you discover several things aren’t working, the problem might not be a single blown fuse, and you may require a diagnostic inspection to find the problem.

If you find that it is only one thing not working, it's more likely a blown fuse is the issue. Of course, you can still check your fuse boxes; you might be unlucky enough to have several fuses blown at once!

Finding your fuse boxes

Most modern cars have two fuse boxes: one under the bonnet and another under the dashboard. The second fuse box may be accessible via the glovebox or be close to the steering wheel. Some cars may also have a fuse box in the boot.

If you can’t find your fuse box, look in the owner’s manual, which will have all the information you need to know.

Before you get to work, make sure your ignition is switched off.

Checking and changing your fuses

When you open your fuse boxes, you should have a chart on the inside of the lid, highlighting all the fuses and what they do. The chart will also highlight the amperage of the fuse. You must replace a blown fuse with another with the correct amperage. If you buy a second-hand car and have issues with blown fuses, it may be that they hadn’t previously been replaced correctly.

Fuses in most modern vehicles will look like a blade and be plugged into the fuse box like you would plug an appliance into the wall. Fuses may be different in size and will usually be colour-coded based on their amperage. You can check these fuses by looking through their window and will easily be able to tell if the fuse has blown.

If you need to replace the fuse, you’ll usually be able to pull it out and plug the new one in. If you can’t pull it out by hand, and there isn’t a plug puller included in your fuse box, a pair of tweezers will do the trick.

If your vehicle has tubular glass fuses, they’re blown if they’re black inside or their filaments are no longer intact. If you can’t remove these by hand, use a small screwdriver or set of pliers.

It’s best to lift one of the end caps first before removing the fuse, or prying the fuse gently from one end, as you want to avoid breaking the fuse itself. Once you have removed the fuse, you can easily press in the replacement.

Testing your electrics

Once you’ve replaced a burnt-out fuse or fuses, close the fuse box, switch on the ignition, and test the part that wasn’t working.

If it works, job done. If not, you may need a more comprehensive check of your electrics, in which case it’s best to find a mechanic who can conduct a diagnostic inspection.