The electrical part of the car includes fuses, which are designed to protect the electrical circuit in the event of any breakdown. How do they look? Every driver has seen the fuse box, and most car owners periodically face the need to replace these elements. But there are often other situations when the fuse is not just blown, but such a disaster occurs regularly. It is not good. Let's try to understand the reasons and find out how to correct the situation.
The main reasons for fuses failure
Among the basic reasons, several can be identified. Some of them are very serious, others are quite simple and banal. For example, a typical situation is when a fuse installed in the side light circuit fails. As soon as the driver turns on these lights, they immediately go out. And the reason in this case is completely simple and absurd - it burned out because it had less power. Let's try to highlight the main reasons why these elements fail and ruin the lives 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 sufficiently fixed, then there is a high chance that the plastic parts of the fuse will melt. Such an element will definitely fail.
In order to solve this problem, experts recommend purchasing a product from another company, which is better known as a manufacturer of components for automotive electrical systems.
But replacing an element with a better and more expensive one does not always solve the problem. Sparks may occur due to oxidized burnt contacts. 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.
Wear
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 is indeed increased voltage in the on-board network, the part will burn out immediately. However, when all parameters in the electrical network are within normal limits or exceed the norm only slightly, the fuse part of the fuse may burn out little by little.
The cross-section decreases every time even with minor overloads. At one point, the part will completely collapse. That's why the fuse blows - you don't have to completely disassemble the whole car. The reasons may be quite simple.
Incorrect choice
This is also a simple reason, but it also leads to unpleasant situations. Often salespeople in stores do not know what they are selling well enough. Also, not every car owner knows the laws by which electrical circuits operate. A situation often occurs when the fuse is incorrectly selected for the current in the network. As a result, it cannot withstand the load in the circuit in which it was included. Once the current is applied, the fuse will blow.
Power surges
Voltage surges may occur in the on-board network of vehicles in which safety elements operate.
Due to these surges, fuses can also fail. This can be observed when the electric motor, on which the elements of the electrical on-board network depend, is blocked.
Violation of the scheme
If a fuse has 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 provided, the resistance drops. So, more current will pass through the element, and not the one for which it is designed. Most automotive electrical systems are not designed to withstand high loads. That’s why fuses are used there, which will save electronic devices in case of critical situations.
Short circuits
This is one of the serious reasons. If opposite polarities come into contact in any way, a short circuit will occur. For this reason, the heater fuse often blows. And it will burn until the owner replaces or insulates the damaged wires.
Short circuits can occur in any part of the vehicle's electrical system. Many people complain that the fuse that protects the cigarette lighter fails. The first thing you should do is not disassemble the connector, take it out and go for a new one. Everything could be much simpler.
If it is a cigarette lighter, then the issue may be the high power of the device that is connected to this cigarette lighter. It may also be a matter of 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 using radical measures, you first carefully examine the design of the cigarette lighter and find the weak point. Usually there are such places - a short circuit can easily occur in them. It is necessary to carefully inspect the contacts and, if possible, somehow insulate them. Usually, after the weak point is found and the cause of the short circuit is solved, the cigarette lighter fuse no longer blows.
Diagnostics
The cost of fuses is very affordable. Most people carry them with them - there is a whole set in the trunk. They can be easily installed into the block if necessary. The situation when a fuse fails is quite normal, since even the most reliable circuit is not protected from surges in voltage and current. If these burnouts happen very often, then a thorough diagnosis is needed.
If any of the fuses burns as soon as they are installed in the circuit, then the first step is to find out which device is causing this. To do this, you should look at the technical documentation for the car to find out which devices are in the circuit with this fuse. Then all consumers that interact with this element are included.
Next, take a screwdriver with a well-insulated handle and touch its metal part to the terminals into which the element is installed. If there is a spark, then there is a fault 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 blew. The last disconnected device is to blame.
on the road?
If the problem happened while driving, and there is no spare fuse, then the situation can still be solved using improvised means. Instead of a safety element, you can use a piece of foil from a pack of cigarettes.
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 a VAZ fuse blows. This will not only improve the operation of the on-board network, but will also protect the circuit from overloads. Some people use wire, but it doesn't provide as much protection. Coins, paper clips, and other metal inserts will remain intact in the event of a critical situation. 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 in place of the burnt one.
How to buy a quality fuse?
These components 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.
Since it is not possible to check each of the elements 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 note "Bosch", "Hella", "Vibe" and "Sound Quest". When purchasing products from an unknown company, you should first check them and only then install them on the machine. You can check it simply - connect the new element to the battery. If it burns 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 install it on the machine - it will not be able to protect electrical appliances in the event of increased current.
How to replace?
Replacing a burnt out element is quite simple. To do this, you do not need to have specialized tools and knowledge. First you need to find the location of this element. Where could he be? And the fuses are located in different places. In some cars they are under the hood, in others - in the area of the front dashboard. They are hidden under the lid. After opening it, you can remove the burnt element with two fingers and install a new one in the same way.
Conclusion
These are all the main reasons. A fuse blows, which means you need to look for a problem. It can be simple and banal, or complex, and finding it will not be easy. It is best to have new protective elements in stock. Then you won't have to hiccup through foil, candy wrappers or paper clips. You can notice the fuse and move on.
An unpleasant feeling arises in a person when suddenly one or another electrical equipment suddenly stops working (lights went out in the house, a group of sockets stopped functioning, the radio in the car does not turn on, etc.) There are many reasons for this, one of which is the occurrence of a short circuit in the electrical chains. The intended protection against such excessive current increases is to blow the electrical fuse. It is this that guarantees the electrical safety of both you and your electrical equipment.
What exactly happens when a fuse link burns out? Now let's try to figure this out. So, a little theory. As is known from physics, when an electric current passes through a conductor, namely the ordered movement of electrically charged particles (electrons), a natural transfer of part of the energy occurs to the atoms of this conductor. And heat, as a physical phenomenon, is the intensity of movement of elementary particles of matter. That is, the more active the particles of a substance move inside the material, the higher its temperature will be, which constantly flows from a higher value to a lower one (trying to balance throughout the entire volume).
Any electrical fuse consists of the following structure: a fuse body with contact clamps, a fuse link consisting of a dielectric high-temperature material and a filament of an easily melting conductor (designed for a certain value of rated current). The body itself serves for fastening both it and on it. Electrical wires are connected to it, which pass inside through a fuse-link. The fuse link is designed to burn out quickly by melting the inner strand of the conductor as the temperature increases due to excessive current.
Simply put, this is why a fuse blows - somewhere in the device a contact accidentally occurred where it should not have been in any case. This naturally created a sharp decrease in resistance in a certain electrical circuit. And according to Ohm's law, as the resistance decreases and the voltage remains constant, the current increases.
The reasons for the combustion of the fuse link lie precisely in the increased current value. It’s one thing when this short circuit is caused once, for example - you plugged a plug into a socket, the power cord inside of which has damage to the external protective insulation and the power wires touch each other (which should not happen under any circumstances). You “stuck” the plug in, there was a “bang” in the socket, and the electricity went out - this sometimes happens to many people. They stuck the plug out (if it was not welded to the socket), went to the electrical panel, replaced the burnt plugs or turned on the circuit breakers, hurray, the light is back on.
It’s another matter when a short circuit between conductors occurs somewhere inside the device and you don’t even suspect it. Naturally, when you turn it on, there will be a blackout, the fuse will burn out (or another type of electrical protection will trip), and when you turn it on again (after replacing the burnt fuse links), the same process will repeat again. In this case, you need to look for the location of the short circuit. You should start with the input circuits (incoming and outgoing wires), and then disassemble and check the electrical equipment itself, in which electrical fuses constantly burn out. As soon as the cause of the short circuit is eliminated, the fuse links will immediately stop burning out.
A blown fuse in a car is a sign of a short circuit. But it happens that they burn out for other reasons. Let's consider all cases.
The first thing to do when a fuse blows is to make sure there is no short circuit. If the check shows that there is no such phenomenon in the on-board network, then the following options are possible:
Too much load on the fuse
The cause of a blown fuse may be the connection of abnormal power equipment to the power line. For example, if you install 100-watt lamps in the headlights instead of the standard 55-watt ones, then with a high degree of probability you will have to change the fuse, since the “regular” one will constantly burn out.
The same situation can occur if an abnormal load on the fuse occurs “independently”. For example, when electric drives move poorly and jam, the current in their electric line increases and the fuse may blow.
Incorrect fuse rating
A fuse that is too low will blow. If you put the same one, but 5 Ampere, in the socket where there should be a 20 Ampere fuse, it will burn out at the first load. In this regard, it is worth knowing (table of denominations at the link).
The opposite situation, when the fuse is too strong, is much more dangerous. In this case, it can withstand increased current for which the wiring is not designed, which can lead to fire.
Poor quality fuse
If you buy fuses from an unknown dealer on the side of the highway, then anything can burn out, even your car. Unknown manufacturers, unknown brands, low-quality fuses, etc. are not for those who love their car. Buy fuses only from trusted auto stores!
Perhaps the most difficult situation is when a fuse burns out from a short circuit, but it is not stable, but occurs from time to time, for example, from accidental contact of a loose contact. In this case, long and very tedious work awaits.
An unpleasant feeling arises in a person when suddenly one or another electrical equipment suddenly stops working (lights went out in the house, a group of sockets stopped functioning, the radio in the car does not turn on, etc.) There are many reasons for this, one of which is the occurrence of a short circuit in the electrical chains. The intended protection against such excessive current increases is to blow the electrical fuse. It is this that guarantees the electrical safety of both you and your electrical equipment.
What exactly happens when a fuse link burns out? Now let's try to figure this out. So, a little theory. As is known from physics, when an electric current passes through a conductor, namely the ordered movement of electrically charged particles (electrons), a natural transfer of part of the energy occurs to the atoms of this conductor. And heat, as a physical phenomenon, is the intensity of movement of elementary particles of matter. That is, the more active the particles of a substance move inside the material, the higher its temperature will be, which constantly flows from a higher value to a lower one (trying to balance throughout the entire volume).
Any electrical fuse consists of the following structure: a fuse body with contact clamps, a fuse link consisting of a dielectric high-temperature material and a filament of an easily melting conductor (designed for a certain value of rated current). The body itself serves for fastening both it and on it. Electrical wires are connected to it, which pass inside through a fuse-link. The fuse link is designed to burn out quickly by melting the inner strand of the conductor as the temperature increases due to excessive current.
Simply put, this is why a fuse blows - somewhere in the device a contact accidentally occurred where it should not have been in any case. This naturally created a sharp decrease in resistance in a certain electrical circuit. And according to Ohm's law, as the resistance decreases and the voltage remains constant, the current increases.
The reasons for the combustion of the fuse link lie precisely in the increased current value. It’s one thing when this short circuit is caused once, for example - you plugged a plug into a socket, the power cord inside of which has damage to the external protective insulation and the power wires touch each other (which should not happen under any circumstances). You “stuck” the plug in, there was a “bang” in the socket, and the electricity went out - this sometimes happens to many people. They stuck the plug out (if it was not welded to the socket), went to the electrical panel, replaced the burnt plugs or turned on the circuit breakers, hurray, the light is back on.
It’s another matter when a short circuit between conductors occurs somewhere inside the device and you don’t even suspect it. Naturally, when you turn it on, there will be a blackout, the fuse will burn out (or another type of electrical protection will trip), and when you turn it on again (after replacing the burnt fuse links), the same process will repeat again. In this case, you need to look for the location of the short circuit. You should start with the input circuits (incoming and outgoing wires), and then disassemble and check the electrical equipment itself, in which electrical fuses constantly burn out. As soon as the cause of the short circuit is eliminated, the fuse links will immediately stop burning out.
» Why do fuses blow in your car?
Diagnosing fuses and why they blow in your car.
Every circuit in a car's electrical system has a fuse that blows and protects the car's expensive wiring. The fuse serves to protect against:
- short circuit,
- current overload.
- failure of automotive equipment
Its cost is low, which is why they are used as protection.
First of all, in the event of a short circuit, the fuse-link is destroyed, thereby breaking the wiring circuit. Buying and replacing an insert is not difficult or expensive.
Any fuse designed for a certain value of flowing current. Only when this value is exceeded does it burn out. Sometimes the manufacturer installs several fuses depending on the power and number of electrical devices in the machine. When a current flows greater than the rated value, the fuse-link melts, i.e. the fuse trips. Now it needs to be replaced with a new one with the same nominal value.
If you install, for example, instead of 10 A, 16 A, then during an overload the fuse can withstand the excess current, but the wiring cannot. As a result, the fuse link will remain intact, and the wires and device must be replaced. If the fuse is set to 8 A instead of 10 A, then the reliability will increase, but if a current flows, for example, 9 A, it will collapse, although with the previous analogue the circuit would have withstood the overload. Car manufacturers also take into account the power reserve on the electrical circuit.
Exist several driver mistakes when using electrical equipment and fuses. For example, instead of a fusible insert they put:
- a piece of wire
- coins,
- nail,
- other metal objects
This does not provide reliable protection. After all, such objects can withstand very high currents, which can lead to overheating of electrical wiring and, worse, to.
You should also, after detecting a tripped fuse, find out what is causing the overload in the electrical circuit. It may be that there is a problem with the lights or generator. If the replaced insert burns out again, it is necessary to call back the electrical circuit and look for a short circuit in the wiring or vehicle equipment.
On the consumer market there are a lot of low-quality devices that are inserted into the cigarette lighter and cause the fuse responsible for the operation of the cigarette lighter to blow.
Non-standard vehicle equipment and overloading of electrical circuits can also cause fuses to blow.
Identifying a faulty fuse
Cars come with one block and two fuse blocks, usually one is located in the engine compartment, and the second is under the dashboard to the right of the driver.
The block located in the engine compartment is responsible for equipment related to the direct operation of the engine and everything that works together with it, as well as for external lighting.
As you might guess, the fuse box located in the cabin is responsible for all the equipment located in the cabin, including the instrument panel and lighting.
Often, on the covers of these blocks there is an explanation of which vehicle equipment a certain fuse belongs to. It is also possible to determine at random by examining each fuse for its malfunction; in this case, the main thing is to determine in which block it is located.
Fuse repair
What to do if the fuse has failed during the journey? There is no spare one. There is a way out in this situation if you have a thin copper wire. But here it is important to choose the right diameter of the thin wire depending on the nominal value. This piece of wire should be inserted into the tips of the fuse and pressed well with pliers. Please note that you do this at your own peril and risk!
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