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Blow fuse: causes and remedies
Blow fuse: causes and remedies

The electrical part of the car includes fuses that are designed to protect the electrical circuit in case of any breakdown. How do they look? Every driver saw the fuse box, and most car owners periodically faced the need to replace these elements. But often there are other situations when not just a fuse has blown, but such a misfortune occurs regularly. It is not good. Let's try to understand the reasons and find out how we can fix the situation.

Main causes of fuse failure

Among the basic reasons, there are several. Some of them are very serious, others are quite simple and banal. For example, a typical situation is when a fuse installed in the parking light circuit fails. As soon as the driver turns on these lights, they immediately go out. And the reason in this case is quite simple and ridiculous - the fuse has blown. ithappened because he had less power. Let's try to highlight the main reasons why these elements fail and ruin the life of car owners.

Bad connection

When the fuse element of the car's electrical circuit is poorly connected to the block, if the contacts of the element are not fixed enough, then there is a high chance that the plastic parts of the fuse will melt. Such an element will definitely fail.

blown fuse

In order to solve this problem, experts recommend purchasing a product from another company that is better known as a manufacturer of automotive electrical components.

But replacing the element with a better and more expensive one does not always solve the problem. Oxidized burnt contacts can cause sparks. This contributes to the failure of the fuse. And it doesn’t matter what quality the installed element is, what power it has. Sometimes you need to first clean the contacts and improve the connection, and then install a new fuse.


Many people think that fusible elements burn out instantly and immediately. This is a popular misconception - in fact, everything is a little different. In a critical situation, when there really is an increased voltage in the on-board network, the part will burn out right there. However, when all the parameters in the electrical network are within the normal range or only slightly exceed the norm, the fuse part of the fuse may blow out little by little.

fuse blowscigarette lighter

The cross section decreases every time even with minor overloads. At one point, the part will completely collapse. That's why the fuse blows - it's not necessary to completely disassemble the entire machine. The reasons may be quite simple.

Wrong choice

And this is also a simple reason, but it also leads to unpleasant situations. It is not uncommon for shop assistants to not know well what they are selling. Also, not every car owner knows the laws by which electrical circuits work. Often there is a situation when the fuse is incorrectly selected according to the current in the network. As a result, it cannot withstand the load in the circuit in which it was included. It is necessary to apply current, and the fuse is blown.

Power surges

Voltage surges can occur in the on-board network of cars in which safety elements work.

vaz fuse blown

Due to these surges, the fuses can also fail. This can be observed when the electric motor is blocked, on which the elements of the electrical on-board network depend.

Scheme Violation

If the fuse is blown, it is worth looking for errors and irregularities in the supply of current to the circuit. When electricity flows through a smaller circuit than the manufacturer intended, the resistance drops. So, a larger current will pass through the element, and not the one for which it is designed. Most automotive electrics are not designed for high loads. Therefore, fuses are used there, which, in casecritical situations will be saved by electronic devices.

Short Circuits

This is one of the big reasons. If bare wires with opposite polarities touch in any way, a short circuit occurs. For this reason, the stove fuse often blows. And it will burn until the owner replaces or insulates the damaged wires.

why did the fuse blow?

Short circuits can happen anywhere in a vehicle's electrical system. Many complain that the fuse that protects the cigarette lighter fails. The first step is not to disassemble the connector, remove it and go for a new one. Things could be much simpler.

If the cigarette lighter fuse is blown, then the matter may be in the high power of the device that is connected to this cigarette lighter. Also, the matter may be in the quality of contacts. Often, the adapters are Chinese, and the quality of the contacts in them is very low. It is recommended that before applying radical measures, first carefully examine the design of the cigarette lighter and find a weak spot. Usually there are such places - a short circuit can easily happen in them. It is necessary to carefully examine the contacts and, if possible, somehow isolate them. Usually, after the weak point is found and the cause of the short circuit is resolved, the cigarette lighter fuse will no longer blow.


Fuses are very affordable. Most people carry them with them - there is a whole set in the trunk. They can be easily installed in the block if necessary.The situation when the fuse fails is quite normal, since even the most reliable circuit is not protected from voltage and current surges. If these burnouts happen very often, then a thorough diagnosis is needed.

If any of the fuses burns as soon as it is installed in the circuit, then the first thing to do is find out which device is causing it. To do this, it is worth looking into the technical documentation for the car to find out which devices are in the circuit with this fuse. Then include all consumers that interact with this element.

why does the fuse blow

Next, take a screwdriver with a well-insulated handle and its metal part touch the terminals in which the element is installed. If there is a spark, then there is a malfunction in the circuit. Turn off one of the electrical appliances and touch the terminal again. When the spark does not jump, it will become clear why the fuse has blown. The last disconnected device is at fault.

How to solve a problem on the road?

If the problem happened right in the process of driving, and there is no spare fuse, then the situation can still be solved with the help of improvised means. Instead of a safety element, you can use a piece of foil from a pack of cigarettes.

blown cigarette lighter fuse

This is paper-based foil. It is so thin that in the event of a short circuit it will burn out in the same way as the VAZ fuse blows. This will not only improve the operation of the on-board network, butalso protect the circuit from overloads. Some use wire, but it doesn't provide that protection. Coins, paper clips, as well as other metal inserts in case of a critical situation will remain intact. But the device, which is protected by a fuse, will fail. There is a second option, but it will require minimal knowledge of car electrics. So, if any important fuse has burned out, you can take the protective element of the cigarette lighter and install it instead of the burned one.

How to buy a quality fuse?

These elements for cars cost much less than the electrical equipment they are supposed to protect. Therefore, experts do not recommend saving on their purchase. It is better not to give preference to inexpensive dubious models. You need to purchase only those products where all parameters are perfectly met.

oven fuse blown

Since there is no way to check each of the items from unknown brands, when purchasing a similar product, it is better to pay attention to the products of the companies that produce them. Among the most famous manufacturers. Reviews mark Bosch, Hella, Vibe and Sound Quest. When buying products from an unknown company, you should first check them, and only then install them on the machine. You can check it simply - a new element is connected to the battery. If it burned out immediately, then the product is of high quality. If, during a short circuit, the product does not burn out, but melts, then it is better not to put it on the machine - it will not be able to protect electrical appliances in casehigh current.

How to replace?

Changing a burnt element is quite simple. For this, you do not need to have specialized tools and knowledge. First you need to find the location of this element. Where can he be? And the fuses are located in different places. In some cars they are under the hood, in others - in the area of ​​\u200b\u200bthe front torpedo. They are hidden under a cover. After opening it, you can take out the burnt element with two fingers and install a new one in the same way.


These are all the main reasons. The fuse blows - so you need to look for a problem. It can be as simple and banal as it is complex, and it will not be easy to find it. It is best to have new protective elements in stock. Then you do not have to hiccup foil, candy wrappers or paper clips. You can see the fuse and drive on.

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