A situation familiar to many, a blown fuse. In most cases, drivers limit themselves to replacing it with a working one and forget about it until the next trip of one of them, without asking the question why the fuses blow.
The task of the fuse is that it takes the “fire” upon itself, in other words, at the cost of its “life” it saves expensive automotive equipment.
If we look at the issue more deeply, then each alarm should alert the car owner, since it happened for some reason. Let’s say that if it was a short-term voltage surge, when the relay-regulator was a fraction of a second late to extinguish it, then the fuse of the protected circuit, where there are problems, tripped. Although the fuse could blow due to problems with the fuse itself, namely the condition of its terminals where it is inserted, or the ends of the fuse itself being already badly damaged. This applies to finger fuses.
A fuse that has a band formed at the point of contact with the terminals where it is inserted will either pass current at times, or not at all, since in this condition the fuse in this place either has very poor contact or is completely absent. Then, if the fuse is visually in good working order (the fuse strip is intact), the circuit will not work, since no voltage will pass through the belt.
In the event that a newly installed fuse blows again, you need to gradually disconnect all consumers that this fuse protects. It is not worth inserting a fuse every time you turn it off, as it may burn out immediately. To check, touch the ends of the fuse mounting terminals with a screwdriver; if you see sparking, then continue to disconnect the next consumers “hanging” on the blown fuse, checking each time for sparking.
Disabling the consumer where there is a problem will restore the protection of the protected circuit, the fuse will not blow. All you have to do is fix the problem in the disconnected consumer that caused the fuse to blow.
Surely many have seen that instead of a fuse there is a coin between the terminals. The coin, of course, cannot burn out and can withstand a very high current, but it can lead to failure of the element in the protected circuit. In addition, it is so close to a fire that suitable wires will heat up until the insulation melts.
Instead of a blown fuse, after eliminating the cause, always install a fuse of the “native” rating. In the absence of a fuse, its integrity can be temporarily restored with cigarette foil. Good luck!
It is impossible to imagine a modern car without a huge number of electronic systems that monitor and manage the basic parameters of the car. For the operation of all electronics, both standard and all installed ones, additional electricity is required, which is supplied to consumers through hundreds of meters of electrical wires. To provide maximum protection against power surges, which are often caused by faulty wiring, every vehicle is equipped with a "set" of fusible protection devices.
The sole purpose of any of them is to protect electronics. At the same time, if it is triggered, it burns out, and thereby opens the electrical circuit, stopping the supply of electricity to the device. Accordingly, after any short circuit or overload in the vehicle's electrical wiring, the fuse must be replaced. In addition to a short circuit, improper use of the on-board electrical network, for example, simultaneous connection of several energy-intensive devices to the cigarette lighter, can also lead to a burnout of the device.
MAIN CAUSES OF FUSE BLOCKING
Frequent burnout of protective devices in a car cannot be considered the norm, since it indicates existing malfunctions. Some of the most common problems include the following:
Of course, the design of the fusible “protector” was initially designed for its one-time operation, but if a fuse protecting the same group of devices constantly burns out, this is a serious reason for checking. Quite often the following situation occurs - a newly installed fuse blows out almost immediately. In this case, the car owner needs to find out which electrical appliance is causing this problem.
In such a situation, it is not necessary to take the car to a service center; you can determine the cause yourself. To do this, you should gradually turn off all electrical appliances that are protected by the “problem” fuse. Each time the device is turned off, do not remove the device, as it may burn out. It should be checked in a simpler way - with the end of a screwdriver with an insulated handle, you need to touch the fastening terminals; if sparking is observed, disconnecting consumers should be continued until it stops - the device being turned off at this moment is the reason for frequent replacement of the fuse.
HOW TO IDENTIFY A BURNT FUSE
Before identifying a blown fuse in a car, you should prepare a tester or indicator screwdriver. The first method of checking involves removing it from the socket, visually inspecting it and checking it with a tester. It is almost impossible to visually determine the performance of such a device, so the use of a tester is mandatory. The handle of the device is installed on the diode sign, the probes are applied to the contacts.
With the second method of checking, there is no need to remove fuses from the socket, which is more preferable for most car owners. Before checking, you need to turn on the circuit in which the malfunction is noted - for example, turn on the radio or headlights. After this, using an indicator screwdriver, you must alternately touch the terminals of one terminal of the “protector” being tested, then the other. If there is voltage on the first one, but there is no voltage on the second one, a burnt-out device has been found.
It should be immediately noted that it is highly advisable to have a spare set of fuses of different ratings, and before replacing a fuse, you must select exactly the same rating. If a lower value is selected, the fuse will blow; if a higher value is selected, consumers connected to this circuit will suffer. For ease of quick replacement, all “defenders” have a different color, corresponding to their “power”.
CHOOSE THE FUSE CORRECTLY
Since the fuse performs a very important function - it insures the car’s expensive electronics against failure, such a “protector” should be chosen extremely carefully. Taking advantage of the fact that when buying one or two “penny” protective devices, the majority of car owners do not pay attention to their quality, unscrupulous sellers or manufacturers try to sell goods that do not meet any quality standards.
Of course, it is very difficult to distinguish a quality product from “garbage” by appearance. You can use the following method to check. You need to connect one of the purchased fuses to the battery. A quality product will be indicated by its rapid burnout. If it starts to heat up and melt, using it in a car is extremely risky - if it is overloaded, the electrical circuit will not open, which can result in either failure of the electronics or a fire.
The other extreme, which car owners often resort to - the use of bugs, can lead to equally sad consequences. The designs of such devices can be very diverse - from wire wound around the ends of a burnt-out device, to a coin inserted as its replacement. Such “homemade products” pass current of any magnitude, since they cannot burn out, which leads to dire consequences, especially for foreign-made cars.
INDEPENDENT REPLACEMENT OF FUSES
Replacing a burnt-out device with your own hands is a matter of just a few minutes. Naturally, in order to avoid subsequent replacement of the entire fuse box, this simple manipulation should be taken with full responsibility. After accurately identifying the source of the problem, replacing the fusible protector should begin with selecting a new one that exactly matches the damaged one. For ease of “identification”, all devices have a different color - in accordance with their power.
It is best to purchase fuses in advance, without waiting until one of them fails. At the same time, you should be based not on your own preferences and cost, but on the recommendations of the manufacturer. If they are not available for sale, it makes sense to place an order and wait a little rather than put your car and yourself at risk. As a last resort, temporary use of fuses of suitable size and characteristics is allowed. A detailed algorithm of actions for correctly replacing a faulty fuse can be seen in the video:
Traditionally, increased attention must be paid if the cigarette lighter fuse has blown - as a rule, in a modern car it is subject to quite a serious load. Accordingly, not only should the cigarette lighter fuse be replaced promptly, but also an independent diagnosis of the causes of the incident should be carried out. At a minimum, you will need to evaluate the feasibility of using a cigarette lighter to charge several electronic devices at once.
CORRECT WIRING, OR HOW TO AVOID REPLACING A FUSE
The fact that occasionally a car's fuses will blow is not a cause for serious concern. A reason to think arises when such a situation repeats itself too often. In order to understand that the fuse has burned out and needs to be replaced, you do not need to be an expert - in this situation, those electrical appliances for which the damaged “protector” is “responsible” stop working.
For an experienced driver, the question “how to find out if a fuse has blown in a car” is not difficult, but to understand why it burns out, especially the same one, is a more difficult task. The first step is to check all the wiring in the engine compartment, or rather the integrity of its insulation.
You should be especially careful with the onset of frost - some types of automotive insulation simply cannot withstand, crack and cause a short circuit, which is the answer to the question of why fuses in a car burn out. Naturally, finding problem areas in the wiring requires a lot of work, since the breakdown can be masked by dirt, and it is not always possible to find it right away.
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.
Fuses are available in any car and in many models of electrical equipment, because if a short circuit or overload occurs in the electrical network, the equipment may well fail.
Their main function is to open the electrical circuit in cases where the current strength in it exceeds all permissible values.
This means that fuses can provide effective protection for both electrical equipment and wiring.
If used, the risk of fire and short circuit is reduced to zero.
And the main advantage of fuses is that they cost pennies, but protect expensive equipment.
If the fuse fails, then replacing it has nothing to do with serious financial investments and installation difficulties.
True, you need to replace a blown fuse with its rated equivalent. Because its defining characteristic is the current strength.
When the fuse trips, it becomes unusable, that is, it turns out that it takes on all the electrical shock that occurs in the network.
There are more powerful fuses, the effect of which does not extend to a separate electrical appliance or a small electrical network.
And for one or several rooms, or even an apartment.
Current strength and its effect on fuse operation
In cases where the current strength has an effective value exceeding the permissible value, the fuse operates one hundred percent.
And a personal fuse having the appropriate rating is installed in the circuit of each individual equipment.
When a fuse-link designed for a lower current strength is installed in an electrical circuit, it is capable of operating at a reduced current value.
Of course, such a fuse can provide protection to other devices, but it will need to be changed more often.
And when a fuse insert designed for a higher current strength is installed, no one can guarantee that the current passing through the circuit may be higher than allowed for the devices.
This means that these devices will simply burn out, and the fuse will not fulfill its task.
Specifics of fuse replacement
To replace the fuse insert, you must first find out the reason for its burnout.
Typically, such an unpleasant phenomenon occurs when the integrity of the wires is damaged or as a result of equipment failure.
If the generator and electrical networks malfunction, fuses can also blow.
Determining which fuse has blown is very simple, even without special equipment: if you suspect that a specific fuse has blown, you just need to remove it from the socket and put, for example, a screwdriver in its place.
How not to do it.
Equipment that was turned on in advance must be turned off in a random order.
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 intended, 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 stove 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. They 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 either simple and banal, or complex, and it will not be easy to find it. 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.
