The headlight sweats what to do. Phenomenon from within. Step-by-step instruction. How to deal with fogging headlights fogging headlights what to do

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Headlights are a component not only of the appearance of the car, but also of your safety. The quality of illumination of the roadway in the dark depends on their condition. The design of optics becomes more complicated every year. At the same time, more and more motorists are faced with the problem of fogged headlights. What to do in such a situation and what are the reasons? We will talk about this in our today's article.

Which cars are prone to this flaw?

Unfortunately, absolutely any car is susceptible to this problem. So, headlights sweat on "Kalina" (what to do, we will consider further), on "Prior", "Grant", as well as on cars of foreign production.

Fresh cars with a mileage of less than 30 thousand kilometers (for example, "Kia Optima") are no exception. If headlights sweat on a new car, what to do? In this case, the problem can be solved through a warranty. But on older machines, this issue will have to be resolved on your own. If the headlight on the Solaris sweats, what to do? Let's first look at the design of the optics in general terms.

About headlight device

On all modern cars, it is a one-piece monoblock. It combines the following components:

High beam.
Low beam (halogen lamp or xenon and lens).
Integrated turn signals (not on every car).
Running lights (often installed as an option, for a fee).

The body and the diffuser are made of plastic. As for the front "glass", on many cars it is also made of plastic. But there are also glass models. By the way, they do not grow cloudy over time, like their counterparts, according to the reviews of motorists. But no matter what surface was applied (plastic or glass), any headlight has ventilation holes. They have special valves with dampers. Through them, all deposits that accumulate in the body over time are removed.

The main reason the headlights fog up is the process of transition from one liquid state to another under certain circumstances (in this case, we are talking about a decrease in temperature). In this case, moisture turns into a liquid state and settles on the surface with the lowest temperature. This surface is the headlamp glass.

Where does condensation come from?

It is formed in the housing due to temperature changes. Moisture in the air begins to accumulate on the surface due to the low ambient temperature and the high inside the headlight. This happens especially often with halogen optics. Such bulbs heat up much more than xenon or LED bulbs. As a result, drops appear on the walls of the glass. This is a natural process, and with a working ventilation system, there should be no consequences. But if there are problems with the optics (which ones - we will consider further), the headlight will inevitably sweat and become cloudy.

Causes

Experts identify several reasons for the occurrence of condensation:

Violation of the design of the optics. This can happen due to an accident. The integrity of the headlamp does not yet guarantee its tightness. As a result, the headlights on the inside of the car sweat. What to do in this case? There are several options - this is repair or replacement. But since modern optics are very expensive, you can try to restore the old one. But this does not give a 100% guarantee - you may have to replace the entire unit. Also note that foggy headlights are a bad sign when buying a car "hand-held". Perhaps it was a "drowned man", or the car was involved in serious accidents, where a violation of the body geometry is possible.
Tuning is not technology. Recently, more and more motorists are installing xenon and "angel eyes". But the very next day the result is disappointing - the headlight begins to sweat and distort the light. This is a consequence of incorrect parsing of the optics. When installing glass, it is important to completely clean the joints from the old sealant. Even the slightest gap will cause condensation to accumulate inside. Some damage the unit mechanically during disassembly. To eliminate this, the headlight is placed in the oven. This is to soften the sealant. At room temperature, the factory seam is very tight and almost impossible to remove.
Poor fit of bulbs. In the case of an abnormal xenon installation, this may be a leaky hole for the ignition unit. This commonplace phenomenon can be a reason for the accumulation of moisture on the walls of the headlights.
Ventilation ducts. Over time, they simply become clogged. As a result, moisture cannot leave the unit and condenses on the glass walls. "Priora" especially suffers from this.

What to do if the headlights on the Prior are sweating, we will tell you specifically at the end of the article, but for now we will give recommendations on how to get rid of this problem in general.

What are the consequences?

The first problem is appearance. Foggy headlights significantly impair aesthetics. But this is not the only problem. When light hits the droplets, the beam is distorted. Lighting becomes weak and uneven, which is fraught with emergency consequences. If the problem is ignored for a long time, moisture will begin to corrode the diffuser. In the case of plastic, it will turn black. Metal simply corrodes.

And if the glass is made of plastic, it will become cloudy. And polishing will not work to fix this problem. The headlight will grow cloudy from the inside. Also, moisture provokes oxidation of the contacts on the lamp. At one point, the optics simply do not light up or go out on the go.

Headlights sweat - what to do?

As we noted above, there are only two ways - repair or replacement. The first option is more economical, but not always effective. However, as practice shows, the problem in 70 percent of cases can be solved without replacement. All we need is a home hair dryer, protective gloves and a sealant. The latter must necessarily contain silicone. The color is not important (but black will stand out the least).

Preparation

So our headlights are sweating. What to do? It is advisable to carry out repair work in a closed room (for example, in a garage) with good light. This way we can easily identify the "breakdown" locations. So, open the hood and inspect the seam on the surface. Usually, depressurization occurs due to a loose fit of the glass or cover.

The latter is located on the back of the block. We open it and turn on the hairdryer. This will remove all the accumulated moisture inside. Be careful - in the case of plastic glass, you can melt the structure. Test the surface with your hand periodically. If the headlight cannot be touched, take a break. Otherwise, the plastic may melt. Depending on the scale of the "tragedy", this operation will take from 3 to 15 minutes.

Some people advise leaving the lights on overnight to dry out the headlamp cavities. But you should not do this - you will strongly discharge the battery, and large drops will not disappear. In addition, on modern cars, an annoying sound will emanate in the cabin if you turn on the optics without ignition.

How do I apply the sealant? On-site repair

If a silicone product is used, it is advisable to purchase the product for a gun with a fine nozzle. It will help create a neat and even layer.

Degrease the area with a degreaser before applying sealant. Pay attention to the hidden cavities. There should be no cracks on the block - even if they are not through, it is advisable to process them. If your car is equipped with xenon abnormally, process the installation locations of the ignition unit. In difficult areas, the sealant can be applied through a flexible tube (in a pinch, spread over the joint with your finger through a rubber glove).

If it doesn't help

After the work done, the headlight still sweats. What to do? In this case, you will have to disassemble it completely. Perhaps the depressurization occurred in the lower, hidden part of the optics. We need to remove the grill and bumper. We disconnect the wire chip at the last moment - otherwise the headlight may fall on the asphalt.

Next, we go around with the sealant. Ideally, the glass should be removed and treated with a new sealing element. But in most cases, the problem is solved after surface treatment. Next, we install the headlight in place, connect the wire chip and fasten the entire cladding. At this, the repair can be considered complete. You will no longer wonder “why the headlight sweats from the inside, what to do and how to be”.

About "old-fashioned" methods

During Soviet times, condensation from headlights was removed by adding brake fluid. It is very hygroscopic and absorbs moisture well. But this method should not be used on modern cars. The headlamp may become cloudy and condensation may not be completely removed due to the complex geometry of the optics.

Which sealant is best?

There are several types of sealants that are used to seal automotive optics:

Silicone. Most popular and cheapest. They are used on budget and middle class cars. They are made in the form of tubes, often go "under the gun". The composition has a high temperature range (from -50 to +250 degrees), strength and elasticity. Can be applied in one layer up to six millimeters thick.
Anaerobic. It is used on expensive cars. The product is a kind of tape that hardens on contact with air and provides good sealing characteristics. However, anaerobic sealant is not suitable for embossed surfaces.

Ventilation holes on the "Prior"

If the headlight on the Prior sweats, what to do? Inspect the condition of the vent hole before pouring sealant. On the "Prior" it looks like this.

A transparent cartridge is still installed inside. Some people deliberately cover it with sealant, but this is not worth doing. You can clean it with a slotted screwdriver with a piece of clean rags.

Conclusion

So, we found out why the headlights sweat, what to do in this case and what sealant to use. As you can see, the problem can be solved without completely replacing the optics. This operation will save a significant amount of money and permanently get rid of condensation in the headlights.

Such a phenomenon as fogging of headlights has recently become a real scourge for modern motorists. At autoforums every now and then there is a question: "Why do the headlights sweat?", To which everyone, as it turned out, has his own answer.

In this article, you will learn why headlights sweat and how to fix fogging headlights. If this problem also bothers you - read on and you will learn how to get rid of fogging headlights.

Droplets, which are the very hateful condensation that those who do not know or do not want to know about ventilation and uniform heat distribution have fought and will fight. Well, okay ... Misting occurs, as a rule, in wet rainy weather. Moreover, moisture on the headlights is not only an ugly and at least strange phenomenon for most people, it is also unsafe. The fact is that fogging of the headlights interferes with normal light transmission and often leads to the fact that the headlamp or headlights completely fail and stop shining.

To understand why the headlight fogs up, you need to know how it works.

The headlights of a modern car are a sealed monoblock consisting of a front glass (most often plastic) housing, as well as reflectors. During the operation of light bulbs, as you know, heat is generated, which needs to go somewhere. For heat dissipation, there are special ventilation holes with valves and air dampers. It is difficult to generalize here all the ventilation systems of modern auto-optics, since each manufacturer has its own views on the effectiveness of this system.

Temperature fluctuations and constant switching on / off of headlights leads to an increase in the likelihood of condensation on the inside of the headlight. However, whatever one may say, if the headlamp sweats, there is a malfunction in the headlamp ventilation system or its depressurization has occurred.

Reasons why headlights sweat

1. Violation of the design of auto-optics. Depressurization occurs most often during an accident or after carrying out all kinds of "experiments", such as:, etc. After disassembling the headlights, it is very important to assemble them correctly and not forget about the ventilation holes. Even if the headlight looks completely intact, this does not mean that it really is. The slightest crack along the joint or on the back of the case can cause condensation.

2. Poor fit of bulbs. Such, at first glance, a banal phenomenon, how a badly or crookedly installed light bulb, oddly enough, can cause fogging of the headlights. There may be a gap at the junction of the light bulb and headlight, which is the reason for the appearance of condensation on the inside of the headlight.

3. Clogged ventilation ducts. Over the years, dust and moisture can cement all ventilation, causing the headlight to sweat. There are situations when car owners themselves became the cause of their troubles. So, more than once I happened to meet "smart guys" who believed that the extra holes in the optics were useless and sealed them with everything without hitting them. After that, of course, we got problems with the headlights, which sweated, dimmed and failed.

Headlight sweats - what to do?

First, you need to figure out what is actually the matter, that is, your task is to find the reason why the headlight sweats. This will require a careful inspection, including the dismantling of the headlight.
After removal, very carefully inspect the surface of the headlight and its housing, check the joints, they must be sealed tightly. Try to find the source of the moisture.
If only one headlight sweats, compare it with the second one, which does not have this problem, and try to find the difference, maybe the ventilation hole is closed somewhere.
If the headlight begins to fog up after you disassembled it, most likely the joint is not airtight, in which case you will have to disassemble the headlight again, rinse and clean everything properly, and then assemble it in compliance with all the rules. Check all the gaskets and oil seals, it is possible that something was "bitten" during the assembly.
Crack. If you find a crack in the case, you can try to glue it, but if there is a crack or chip on the glass, replace the glass or headlight completely.
The easiest way to get rid of fogging headlights is to use silica gel. This substance is a transparent granules that effectively absorb any moisture, not allowing it to condense on surfaces. The solution is quite "collective farm" and does not fully solve the problem, however, it is also worth considering as an option. This silica gel can be found in stores and when shopping for shoes.

In any of the above cases, I strongly advise against delaying the repair and troubleshooting, this is fraught with a worsening of the situation and the failure of expensive bulbs. Moreover, because of the poor performance of the headlights, you run the risk of one "fine" moment to be left without light, or even worse - to get into an accident.

Problems with fogging headlights can occur on any type of transport. Initially, they do not pay special attention to condensation in the headlights, considering this phenomenon not particularly significant, therefore, the elimination of the defect is postponed "for later". But we should not forget that the problem can worsen, there will come a moment when an insufficiently lit road in front of the car can cause an emergency, the presence of moisture can even disable the lighting fixtures or cause a short circuit.

Naturally, fogging of headlights cannot be considered the norm, the reason for this is, firstly, a significant decrease in the quality of lighting, it will become what can be obtained from a dirty headlight. That is, it will be quite difficult to notice a pothole on the road, or even a pedestrian.

In any case, it is not recommended not to pay attention to the problem with fogged headlights - sooner or later this situation will entail more complex problems.

The headlight sweats from the inside, which is affected by fogging, what is the danger

Headlamp fogging can cause water to build up inside the headlamp. Since metal parts are afraid of exposure to moisture, corrosion symptoms will soon begin to appear, and in the future, the metal parts of the headlight will begin to deteriorate.

Many manufacturers today are striving to replace metal parts of headlights with plastic ones, however, metal glass is still the material for making lamps.

The proximity of water with a heated lamp may ultimately end up in the fact that the lamp will simply burst.

The lamp can also burn out if water gets on its contacts, which is a good conductor of current. Fuses may also burn out if at this moment the car is on the road - there is a threat that the further path will have to be overcome in the dark.

Constant moisture in the contacts will cause the lamps to burn out constantly.

Condensation in the headlights, headlights sweat, reasons

Fogging of headlights is observed due to the appearance of condensation in them and its settling on the inner surface of the lampshades. To eliminate this phenomenon, you will need to find out how moisture can get inside the headlight, because visually the lighting device looks sealed.

Steam fogging can be caused by the following:

cracks appeared on the plastic housing of the headlight
there was a destruction of the sealant connecting the body with the glass part of the headlight
minor cracks appeared on the glass surface
leakage at the wiring site
clogged ventilation ducts

As a result of faults that are completely different in nature, we get one result - a violation of the tightness of automotive optics. But since the causes of the appearance of condensation can be different, then different methods of eliminating them will need to be applied.

Headlights fogging can be observed both on cars that have already been repaired, and on completely new ones. Moreover, negative manifestations can be observed even if there are no objective reasons that could cause the appearance of condensation.

incorrect design of headlights

In some cars of the Chinese and domestic assembly, where there were serious complaints about the quality of this assembly itself, fogging of the headlights was quite common.

The main reason for this is imperfect design. It is assumed that the assembly should result in a sealed structure, i.e. there should be no access to the airspace inside the headlamp from the outside.

An improperly made headlight traps air from the outside of the car, and its humidity is often quite high. An elevated temperature inside the headlamp and a cooled glass surface from outside are good reasons for condensation to form. Modern cars are no longer equipped with such "blown headlights", but for cars of earlier production, such a malfunction was typical.

the headlight has a fistula

Such a phenomenon as a "fistula" is formed if, when pressing on a headlight, for example, during an accident, it does not break completely, but moves away from the body a little. Outside humid air and sediment water will be drawn into the resulting small hole.

headlight glass microcrack

For the same reasons, microcracks can form on the surface of the glass, as a result, the appearance of fogging.

It should be noted that microcracks are so small that it is rather difficult to notice them with the naked eye. Nevertheless, the troubles arising from their presence will be obvious.

the hydrocorrector is out of order

Although this reason should be attributed to specific, but not impossible. Some types of headlights are equipped with hydraulic correctors. By turning the knob on the control panel, you can increase the pressure, from which the illumination level will be increased, or vice versa, if necessary, it can be reduced in the same way, by turning the knob in the opposite direction.

If the hydraulic corrector breaks down, fluid flows out into the headlight, as a result, we observe fogging. Most often, the owners of domestic VAZs suffer from such a breakdown.

If moisture enters through the non-return valve

Information on the tightness of car headlights should be slightly clarified, because most lighting units in modern cars are equipped with check valves, the task of which is to release excess air that expands when heated by lamps.

If condensation appears inside such headlights, make sure that the check valve caps are present and check that it is working properly.

We watch the video on how to clean the ventilation duct of the headlight:

The desire to save a little on repairs after an accident leads to the fact that car owners decide to install non-original spare parts on the car. And the lighting elements are no exception, because the cost of the original headlight sometimes turns out to be simply unaffordable.

Problems arise if a low-quality Chinese fake is installed. It is sometimes difficult to locate the place of damage; during an external examination, defects are not detected.

There are two options here:

look for damage to the headlight
purchase and install a new one, if not original, then at least more expensive and high quality.

In order to get the desired result as a result of the repair, experts recommend:

at the first stage of work, thoroughly dry the headlight - the moisture remaining inside will cause fogging again
if it is problematic to remove the headlamp, you can use a hairdryer, the hot air emanating from it will allow the headlamp to be rid of moisture.

Humid air can enter the headlamp if there is no rubber or plastic gasket where the light bulb fits to the body.

We are looking for a fistula in the headlights, 100% method for determining a fistula

To accurately determine the presence and location of the fistula, you will need to remove the headlight. Next, pour water into a large container, lower the headlight into it. Observing the process of the appearance of air bubbles will show the exact location of the fistula.

It should be noted, then we dry the headlight, we treat the marked place with a sealant. After the first layer has dried, you will need to apply the second. This procedure will help get rid of condensation inside the headlight.

The budget option for repairing a crack in the headlight glass

Since glass defects are sometimes very small in size, special lighting devices can be used to detect them.

If a chip or crack is found, then the correct option would be to replace the cracked headlamp glass with a new one, but it is not always possible to buy it - in most cases the glass is sold together with the headlamp, extra costs in this case cannot be avoided.

A way out of this situation can be a tint film. In this case, you should choose a transparent film. The adhesive base of the film will allow you to cope with the task without any problems, while all existing cracks will be reliably sealed, and the glass itself will stop collapsing further.

If the crack is large enough, then glass replacement cannot be avoided.

To reduce the cost of repairs, you can try to find the original headlight on parses, but you should look at the degree of glass wear - you may have to polish the glass.

Methods for drying fogged headlights

If they do not want to complicate the repair process, experienced drivers use the method of "dry" elimination of condensate. It is especially relevant if the headlight fogs up periodically. You will need to remove the plafond from the lighting device, loosen the fasteners of the lamps, unscrew them from the holder, but not completely.

Condensation should not appear after this procedure. If it is observed, you will need to use other methods to eliminate it.

Silicone sealants that can be used to seal headlights

If the above process of drying the headlights turned out to be ineffective, then you still need to spend time on a thorough inspection and identifying a gap, cracks or chips.

If found, silicone sealant can be used. It goes on sale in cylinders and is available in any auto shop.

Applying the product is a fairly simple process, it will be easy for every motorist to handle it. If there are problems with determining gaps or chips, it is better to immediately contact the professionals - the masters will easily determine them using optical or laser special devices.

All that remains is to carefully seal the detected defects with silicone.

It should also be borne in mind that the life of sealants is not always long enough, i.e. problems can arise precisely due to the fact that the sealant has lost its original qualities.

In this case, gaps can be formed both visible to the human eye and practically invisible. Most often, middle-class cars assembled in the Middle Kingdom or on the assembly lines of domestic car factories suffer from such problems.

If there is a suspicion that a sealant is the culprit for the problems, there is only one way out, careful application of fresh silicone on all suspicious seams.

Polishing the headlights, as with the help of polishing, eliminate microcracks on the headlights

If a crack is found on the glass, then a polishing method can be used. This will require a grinder and a soft nozzle for it. As a result of polishing, the edges of the cracks seem to "catch" each other.

Synthetic transparent sealants

The second rational option would be to use a special transparent synthetic composition for treating the cracked surface; it is also implemented in car dealerships.

Such compositions are applied easily, dry quickly, do not allow moisture to pass through, and most importantly, they do not interfere with the penetration of the light beam.

At the same time, one should not forget about the rules for applying the material - violations of the technology for applying the synthetic composition will make your work useless.

What to do if water gets inside the machine

It is not necessary to exclude this option from practice. The work in this case will be long and painstaking, it will be necessary to seal the lighting devices from the inside. if there is no experience in performing such work, it is easier to contact the masters of the service station. In addition, such work may require the use of special equipment.

During the renovation process:

the lighting unit is dismantled
disconnects from the car's electrical circuit
the gaps, fasteners, technological holes are sealed with the help of seals, gaskets, sealing compounds.

Certain difficulties in the performance of work can create design features of a particular car model.

The car is under warranty and the headlights are fogging up

It is not surprising that fogging of headlights is never observed in cars such as Porsche, SSC Tuatara or Koenigsegg Agera R, middle class cars are susceptible to it, it is in such models that there are often defects in design, and when they are assembled there is a possibility of violations of production standards.

If the fogging of the headlights is observed on a brand new car that has not yet been in an emergency or has not accidentally rested its headlights on the curb, then the only solution will be the best solution - filing a claim with the manufacturers.

The defect must be rectified during the warranty period free of charge. Of course, the manufacturer has the right to conduct an examination - after all, sometimes inexperienced drivers are the culprits of the problem.

If there is no service center in the village where you live, then you can contact the manager of the car dealership in which the car was purchased, or the dealer.

Pro tip: if all the above methods don't work, what to do

There is one more, so to speak, "folk method", which suggests pouring brake fluid into the headlight to prevent steam from fogging up. Indeed, it will attract water molecules and the condensation will disappear. But the brake fluid will also attract dirt and debris, and eventually the glass from the inside will be covered with a dirty film and will no longer be transparent.

A piece of silicone gel placed in a headlamp will not give a positive result for a long time - it absorbs moisture well, but it expands quite actively, over time it can become so large that it will interfere with the access of light.

You should also remember those tips that can be truly useful and universal, these are:

polishing the headlights, but there is no guarantee that after driving on uneven roads from shaking and vibration, cracks will not appear again
the use of modern transparent compositions, moisture-proof, characterized by good optical properties
replacement of glasses.

Those. it will need to be changed periodically, otherwise it will interfere with the normal operation of the lighting system.

Any car optics has a special ventilation system and it is through such channels that water easily gets into the headlight. To quickly eliminate fogging of the optics, you need to do regular drying. To do this, it is recommended to open the hood of the car for 30 minutes after washing the car. But if the optics of your car sweat for a long time, then this may serve as a signal that your headlamp is faulty. In this article we will try to figure out why headlights sweat and what to do to fix this issue.

How to improve the headlights in the car, I advise.

So what makes the headlight sweat?

The plastic housing of automotive optics is cracked or damaged.
The sealant connecting the glass surface of the headlamp to the body has collapsed.
The tightness at the wiring site is broken.
Small cracks in the glass;
Clogged ventilation ducts that circulate air in the headlamp.

We must not forget that all these malfunctions can lead to only one thing - the tightness of automotive optics will be broken. But depending on the source of fogging on the inside of your headlamp, there are different ways of what to do in this situation.

What can happen if your headlight fogs up from the inside.

If moisture constantly accumulates inside, this can lead to the creation of the so-called "lens effect". As a result, the efficiency of the side lighting can be drastically reduced, which will complicate the control of the car (especially at night).
The presence of moisture has an extremely negative effect on contacts. They oxidize, which in turn can lead to failure of electrical wiring.
Water splashing on a hot surface inside the headlamp can destroy the reflector.
Moisture can lead to corrosion. And soon this rust will cause the metal parts of your headlight to darken and lose their functionality.
Constant moisture inside the headlight will significantly reduce the life of the light bulbs.

What to do if your optics constantly sweats, and why this happens - only the master will tell you in this matter. This requires certain skills and equipment. For example, it is simply impossible to find small cracks on the glass surface of a headlight without special equipment. Therefore, quite often the best option will be if you go to a car repair shop or service center.

But if you want to understand for yourself why the optics of the car sweat and fix this problem, then use the following tips, which can be very useful to you.

How to eliminate fogging headlights with your own hands

Before you decide to start looking for the source of why your headlights began to fog up, wash your car optics well, and then dry them well as well. Then, if they are available, you need to clean the ventilation ducts. Most often, most modern car headlights have access to the ventilation ducts under the hood or under the bumper. If you clean the channels, and the fogging of the headlights continues, then you need to remove the optics from the car. After all headlights sweat from the inside, and it is impossible to fix this problem on the car.

The sequence of your actions should be as follows. First, you need to remove the battery terminals, then disconnect the wiring from the headlight itself, disconnect the fasteners that attach the headlight to the car body, and remove the optics. Thoroughly clean the body from dirt, check if the sealant has collapsed at the joints, make sure that all joints are intact. You can use a magnifying glass to detect the presence of microcracks.

The removed optics must be very thoroughly dried. It is necessary to remove the bulbs from the nests and dry them well as well. It is better to use a hairdryer for this.

If, during inspection, you find small leaks at the junction of the optics with the headlight housing itself, then such places can be restored with exactly the same sealant. If the tightness is damaged more significantly, then it would be best if you:

disassemble the headlight,
completely clean the joint from the old sealant,
this place must be degreased,
apply a new sealant,
fasten the headlight parts.

In addition, you need to carefully go through the sealant along all the joints and connections of the headlamp unit. Particular attention should be paid to the place where the wiring passes into the headlamp.

After you have completed all of the above steps, dry the headlamp thoroughly, wait until the sealant has completely cured, and reinstall the headlamp back on the car.

If large cracks are found on the optics, then it is necessary to replace such a part with a new one. Often, when a car owner decides to repair major damage on his own, on his own, this will not lead to the desired result. Most often, after a short time, the optics will start to sweat again. It must be remembered that the best option for eliminating fogging of automotive optics can only be a complete replacement of the failed optics with new optics.

Sometimes the reason the headlight fogs up from the inside , may consist in the fact that the tightness of the docking terminal for connecting the "turn signal" to the headlamp is broken. Then the best option would be if you seal the area with a sealant.

Do not forget that after you remove the headlamp, you need to clean the ventilation ducts. The whole reason for fogging headlights from the inside can only consist of this. Take a thin wire in your hand, "conjure" over the headlamp for half an hour and the problem will be eliminated.

Video - headlight fogging repair

Good luck on the road !!!

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"let's talk about this: Why headlights sweat and the reasons why the headlights sweat. The topic is quite popular, according to the statistics of "search engines", and very relevant for. Therefore, of course, I could not stay aside and not insert my "5 kopecks" ... Let's start with what the fogging of headlights is. This phenomenon manifests itself in the form of small droplets on the inside of the headlight, also called condensation. Condensation, as you know, is formed as a result of temperature changes and the evaporation of large amounts of moisture. Condensation is also the first sign of poor ventilation, which is directly related to fogging headlights.

Fogging headlights most often observed in wet weather (during rain, fog or snow), when the level of moisture in the air exceeds the norm. In such weather, drivers need headlights like nothing else, but if the headlights sweat, then there will be no sense from them. It is the decrease in the efficiency of headlights that is the main reason why fogging of the headlights cannot be ignored. Reduced visibility in rain or fog conditions can have serious consequences, which often end in disaster. The accompanying unpleasant moments of the "crying headlights" effect is that it looks strange and not aesthetically pleasing. In addition, bulbs, the price of which often reaches the cost of the headlight itself, do not last very long in such conditions. All these unpleasant moments confirm the fact that fogging of headlights is a whole "disease" that needs to be treated urgently, and preferably at its initial stage.

A few words about the headlight device in order to understand why it fogs up

In most cases, the headlights of modern cars are made in the form of a sealed monoblock, which consists of a body and a front glass (glass or plastic). Inside the headlamp are reflectors and bulbs, which you know generate heat during their operation. To remove heat, special ventilation ducts with valves and air dampers were invented. Each car has its own shape of headlights, as well as the principle and structure of the ventilation system, so the ventilation device is described in general ...

From constant temperature changes, as well as frequent switching on and off the headlights, the likelihood of condensation increases, but if the ventilation does not work correctly or does not work at all, fogging will occur, which must be dealt with.

Now about the reasons why the headlights sweat

Depressurization or violation of the block headlight design. The violation of the integrity of the body occurs as a result of an accident or after unsuccessful attempts to tune the headlights. For example, the headlamp is often disassembled when, etc. During such work, it is important not only, but also to collect it at the same time without breaking the tightness and without damaging the ventilation ducts. Even completely intact and sealed, at first glance, the headlamp can have cracks and leaks in the seam. As a result headlight starts to sweat due to the fact that ventilation is disturbed in it, there may be more holes than needed or, on the contrary, less.

Light bulbs (poorly fitting or not fitting). Even an incorrectly installed or matched light bulb can cause fogging of the headlight. At the connection points, a leak occurs through which moisture can freely penetrate into the inside of the block headlight.

If the ducts of the ventilation system are clogged (on purpose or not), or the valves are faulty, fogging of headlights... During vehicle operation, dust and moisture seep into the air vents, resulting in poor ventilation and headlights sweating. Sometimes the owners themselves, unaware of the consequences, seal the holes, as a result, with their own hands, they created a "head" pain for themselves. Some "smart guys" even deliberately close up the air ducts with anything for better tightness, in the end they got " crying headlights"that shine badly and look strange.

What to do if the headlight sweats and how to find the cause?

Well, first of all, you must, of course, find the reason, guided by the above information. To do this, you first need to visually inspect the headlamp, as well as its ventilation holes. In most cases for this.
After you have removed the headlamp, make a close inspection of the headlamp glass and its housing, and also pay due attention to the joint. There should be no cracks on the glass and the case, I think this is understandable. The joint must be sealed, even the slightest hole can cause the headlight to fog up.
If you only have one headlamp sweating, try comparing it to a second headlamp that does not have this flaw, you may see differences in assembly or vents.
It happens that headlight sweats after some work was done on it (disassembly, repair, etc.). In this case, most likely, the joint is not glued well enough, the problem can be solved by re-disassembling and re-gluing the two parts of the headlight. Make sure there is no misalignment, seals, oil seals or other rubbers.
If the assumptions with a crack on the case are confirmed, try to glue it, or replace it with a new one. A crack on the glass, most often, cannot be repaired or afterwards it looks, to put it mildly, ugly, so the solution is to replace the headlamp glass or completely replace the headlamp.

An alternative way to solve the fogging problem

This method is quite simple, however, I note that it does not eliminate the cause of fogging of the headlight, but only temporarily solves the problem of fogging. There is a special absorbent called "silica gel", the task of which is to absorb excess moisture, preventing it from settling on surfaces. So, bags with such silica gel can often be found in the shoe industry, or other industries where moisture is unacceptable. Even if the solution smells like a "collective farm", it still, in the absence of anything better, allows us to solve the problem of fogging. The sachet or sachets (depending on the size and intensity of fogging) are placed inside the headlight housing, after which the headlight is assembled and as a result sweats less or all stops sweating. How long the effect will last, I cannot say, it all depends on the weather conditions and the intensity of fogging.

Let's summarize ...

Fogging headlights- an unpleasant problem that needs to be addressed immediately. Any delay or delay can cost you dearly, at least a malfunction of an expensive light bulb or optics, and at most - an accident as a result of poor visibility. Even if you don't get into an accident, a suddenly burnt out light bulb while traveling, especially at night, is, you see, a big problem and a nuisance. Therefore, in order to prevent the development of a bad scenario, sweating headlights must be repaired immediately, if not by yourself, then by specialists. In extreme cases, such a headlamp can be replaced completely.

Thank you for your attention and for reading the article to the end. Do you know any other causes of fogging headlights? Share them with us and maybe your advice will help someone solve his problem or even save his life. Until then, and see you next time.