1. Home
  2. /
  3. Tips and Tricks
  4. /
  5. How to Tell If Fuse is Blown in Car? 3 Easy Steps
How to Tell If Fuse is Blown in Car

How to Tell If Fuse is Blown in Car? 3 Easy Steps

You’ve undoubtedly heard the term “blown fuse” referenced at some time or another, either by a technician or by a friend who is knowledgeable about automobiles. But first, let’s talk about fuses: what exactly are they, why are they so vital, and what often makes them blow?

In this article, we are going to discuss fuses, including what they are, why they blow, how to tell if a fuse is blown in a car, and when it is necessary to consult a professional.

What Exactly is a Fuse?

Fuses are a crucial component of the electrical system in your vehicle, and its primary purpose is to prevent circuits from being overloaded by the heat generated by the electrical system of your car. Wires and other electrical components of your vehicle may melt and get damaged or destroyed if there are no fuses in place to control the heat generated by these components. Circuits that are overloaded may, in severe circumstances, ignite and catch fire, which not only results in further damage but also puts your life and the lives of your passengers in danger.

How Long Do Fuses Last?

There is substantial disagreement over the actual lifespan of fuses, with some manufacturers stating that fuses may remain functional for as long as 20, 30, or even 40 years. In the automotive sector, however, it is suggested to inspect fuses after 10 and to consider replacing them if necessary. In spite of the fact that fuses may have a lifespan of more than 10 years, deteriorating components in your car might speed up this process, leaving you with a blown fuse earlier than expected.

Why Do Fuses In Cars Often Blow?

If there is an excessive amount of current flowing through the circuit, the fuse will “blow,” which will cause the ribbon that permits the electricity to travel through to melt and break the circuit. The source of the excessive current is an electrical component that is using more power than it is able to manage; this is often the result of malfunctioning equipment.

The following is a list of some of the most typical reasons why fuses in automobiles blow:

  • Incorrectly functioning switches
  • Wires that are faulty
  • Mechanical issues
  • Flaws in electrically-driven components

How To Determine Whether Or Not A Vehicle Fuse Has Blown?

If one of the lights inside your vehicle suddenly stops functioning or if your indicator isn’t working, there is a good probability that one of the fuses has blown. But what happens next?

Your initial step should be to get in touch with some experienced individuals in the field. Working with the electronics in a car demands professional knowledge along with a steady hand.

However, if you are curious and want to check for a blown fuse in your vehicle on your own, the following DIY procedures would need to be carried out.

  1. Locate The Box Containing The Fuses

It is essential that you identify the section of the automobile that has the blown fuse, and depending on the brand of the vehicle, there might be as many as four fuse boxes spread around the interior and outside of the vehicle. If you need assistance, look in the user manual of your device to learn which fuse box controls which circuit, and then proceed from that point. The fuse boxes are most often found in one of the following places, according to industry standards:

  • In the boot
  • Underneath the back seats
  • Beneath the dashboard
  • Under the bonnet
  1. Identify The Specific Fuse

After you have found the faulty fuse box, the next step is to determine which fuse in the box is the problem. Fortunately, in order to make things simpler, the majority of fuse boxes will feature a detailed diagram that explains the purpose of each fuse as well as its position. If you do not have a check fuse multimeter, you will need to make use of a test light if your fuse box does not already come equipped with this convenience feature. (At this point, things are becoming quite technical, and it would be in your best interest to leave this to the professionals!)

If you are going to utilize the test light approach, however, you need to make sure that you choose a test light that is computer-safe and has an LED light. Just turn the key in the ignition, but leave the engine turned off.

As soon as the ignition is turned on, connect the clip that comes with the test light to any metal that is visible. The probe should then be used to make contact with each end of each fuse.

  • In the event that the fuse is operating as it should, the test light will glow from both sides.
  • In the event that the fuse has blown, just one side will light up.
  1. Take Out The Fuse and Inspect It

Once the engine has been turned off entirely, locate the fuse that has to be removed and do so by grasping it with a fuse puller. In the event that there isn’t one readily available, a reliable set of needle-nose pliers will also do the job.

After it has been removed, the fuse may then be looked at more closely. Holding the fuse up to the light while maintaining your grasp with the puller, examine the inside of the see-through housing. You need to look in there and find a tiny metal wire. In the event that the wire can no longer be seen as a single piece and instead looks to be damaged or split in two, the fuse has in fact “blown.”

What Should I Do If My Fuses Continue To Blow Even After They Have Been Replaced?

If you find that you are constantly replacing fuses, there is most likely a more serious problem occurring with your system. If you have already changed your fuse and carefully verified the amperage and circuit, yet your fuse continues to blow or your electrical components do not function, it is possible that your vehicle has a short circuit.

There are two main causes that are responsible for the majority of short circuits:


Motors and other components are necessary for the windshield wipers, power windows, air conditioners, and other features on your vehicle to work correctly. If these components are damaged in any way, the components may need a greater amount of power in order to work as they normally would. This may result in an increase in the flow of electrical current, which can lead to a short circuit.


Your system may have a short circuit if it has frayed or exposed wires, especially if those wires come into contact with metal or other things that inhibit the passage of electrical current.

In any of these scenarios, taking your vehicle to a trained technician for automotive repair is the better and more prudent course of action. Because you do not know the extent of the damage, it is imperative that you get your electrical system rectified as soon as possible in order to ensure everyone’s safety, including yourself and the other drivers on the road.

The Bottom Line

We hope by now you have a fair idea of what a fuse is, why it blows, and how to tell if fuse is blown in car. Even though we have shared with you the DIY steps to fix the issue, if you face any problem or confusion, automotive professionals at the Car Expert Group are always available to assist you and make your driving safe, secure, and easier than ever

Recent Posts