DIY wireless keyboard repair. The keyboard doesn't work. Keyboard doesn't want to work in BIOS

If for some reason (the keyboard was filled with liquid, debris got between the keys) some keys on the keyboard stopped working, then you should not immediately run to the store for a new one. You can try to fix the keyboard yourself.

How to fix a keyboard after it gets water?

If water or any other liquid gets into the keyboard, then do not panic, but calmly follow the tips below:

Turn off the computer's power.
Disconnect the keyboard from the computer system unit.
Turn the keyboard over and shake out the liquid.
Using a screwdriver, unscrew the screws and remove the keyboard cover.
Carefully remove the board and all films with contacts. On some models, you must first remove the buttons before you can remove the films. The buttons are removed using a thin object (knife, small screwdriver).
Taking care not to damage anything, use a cotton swab dipped in alcohol-containing liquid to wipe all plastic parts of the keyboard. The board must be cleaned with a dry cloth.
Remove any debris that has gotten into the keyboard.
Dry the keyboard, buttons, circuit boards and films thoroughly.
Assemble the keyboard and install the buttons.
Connect the keyboard to the computer and check its functionality.

In this way, you can repair any keyboard if water or some other liquid is spilled on it.

How to fix a waterlogged keyboard on a laptop?

The principle of cleaning the keyboard on a laptop is very similar to that described above. The only difference is that the keyboard mounts on a laptop may not be on the bottom with screws, but on the top, on latches, in front of the screen.

Everything is also carefully disassembled, wiped and dried. The main thing is not to rush and not to break the fasteners of the buttons. Also, do not forget in what order the buttons are installed.

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Blue screen of death - what to do?

The Blue Screen of Death causes panic among inexperienced users, although in fact this name for this computer malfunction is slightly exaggerated. This article will talk about the possible causes of the Blue Screen of Death and how to eliminate this phenomenon.

What to do if the keyboard on your laptop does not work

Often the keypad does not respond to presses due to incorrect operation of the software. Why the keyboard does not work on a laptop often helps to understand the device's BIOS entry. If navigation through the menu items of the basic I/O system occurs, the next stage of testing should begin.

We go into safe mode and test the device with a minimum set of services, when the drivers are not involved. If the keypad of a laptop computer is functioning, the problem lies in the incorrect operation of the drivers - they need to be reinstalled.

But how to do this if the buttons on the laptop keyboard do not work? To do this, the operating system has an on-screen information input panel, and you can use it. A way out of the situation would also be to connect portable keys to the laptop.

Often the keyboard on a laptop stops working due to liquid spilled on it (water, coffee, tea). To quickly try to correct the situation, you need to turn off the device, remove the battery and dry the equipment with a hairdryer. It is advisable to do this with cold air if the device has this option. Such prompt actions will help slow down the oxidation process of contacts, boards and microcircuits.

How to disassemble a laptop keyboard

Despite the fact that the laptop seems to be monolithic, the keypad can be easily removed from it. If you don't know how to remove the keyboard from your laptop to clean it, these instructions will help you.

After disconnecting the equipment from the power supply and removing the battery from it, you can begin to remove the keypad. To do this, you need to open the latches or unscrew the screws (it all depends on the method of fastening), after which the element can be removed from the case. However, first you need to figure out how to disconnect the keyboard from the laptop. To do this, remove the decorative panel located above the information input device and disconnect the cable. It is connected to the motherboard socket using a special lock, which may have a different design in different models. By opening the lock, the cable can be disconnected from the motherboard.

How to properly clean your keyboard

Dust and dirt inside the keypad of a laptop computer is a common occurrence. This can make typing text and entering other information significantly more difficult. Therefore, an operation such as cleaning a laptop keyboard should be carried out as planned, especially since it is not so difficult to do.

To remove dust from the surface, it is enough to use a soft brush intended for furniture, and to remove debris from under the keys, you should use a vacuum cleaner (preferably a car one). Dirt is usually removed using isopropyl alcohol (never ethyl alcohol, otherwise letters and other symbols can be erased) or cleaning fluids based on it.

How to clean the keyboard on a laptop if, due to spilled liquid, its keys begin to stick? To get rid of this inconvenience, the information input panel will have to be disassembled. Perhaps not completely, but there are definitely problem keys. In order not to damage either them or the mounting location, you need to know how to remove the button carefully. In fact, there is nothing complicated about this - just pry off one of the corners of the key with a screwdriver or a table knife (not sharp) and move to the opposite side at the same level. If you need to remove a large number of elements, it is better to first photograph their location so as not to make mistakes during assembly later. How to clean the buttons on a laptop when they have already been removed is not difficult to guess.

What to do if the keyboard is flooded with liquid

To do this, you can use regular warm water and cotton swabs. After cleaning, be sure to let the keys dry.

Restoring a keyboard cable on a laptop

The keypad is connected to the motherboard using a special cable. If it is not connected correctly or is faulty, you will not be able to enter information. How to remove the cable from the keyboard to check it?

On some devices, this flat wire can simply be pulled out with a little force. In other models, to disconnect the cable, you need to open the locking lock. Since it is often impossible to grasp it with your fingers, you should use tweezers. If the element is not tightly connected or connected backwards, correcting the situation is not difficult.

If the tracks are broken, the keyboard cable will need to be repaired. This operation is quite labor-intensive, requiring skill, experience and patience. There are several ways to repair a laptop keyboard cable, but in each of them it is necessary to strip the insulation, and this must be done using magnifying equipment and special tools. Then it is necessary to lay new paths using conductive varnish. Restoring a train is a jewel-like job, and without proper qualifications you cannot cope with it.

Where to repair a laptop keyboard

It is best to leave repairs to a laptop computer keypad to professionals, as lack of experience can make the problem worse. Moreover, by ordering a laptop keyboard repair from a reliable service center, you are guaranteed to receive impeccably functional equipment again for little money.

Specialists of specialized workshops, in addition to extensive experience, have at their disposal all the necessary tools and devices. In this case, you can repair your laptop keyboard very quickly. Orders, as a rule, are accepted on the service center website, which is very convenient and contributes to a faster response to requests.

How to fix a laptop keyboard?

The compactness of the laptop is both its main advantage and disadvantage. Users often spill tea, coffee, soda and other drinks onto its built-in keyboard - of course, unintentionally.

But due to such an unfortunate accident, not only the keyboard itself can fail, but also the motherboard and other parts of the laptop computer. And, as practice shows, repairing a keyboard on a laptop is somewhat more difficult than repairing an external one. Let's find out how this can be done.

Is it possible to repair a laptop keyboard?

The keyboard can break for various reasons: mechanical impact (for example, the laptop lid was slammed while there was a foreign object on the keyboard), ingress of sweet liquid, buttons falling out, etc. In addition, the keys may not respond to pressing for reasons unknown to the user. Keyboard repair will help you understand them and fix the problem.

Most often, you can fix a button (key) on a laptop keyboard on your own, you just need to know how. Below is a step-by-step description of the keyboard cleaning process:

Before you start repairing your laptop yourself, remember whether it is under warranty.

If this is the case, you can take your computer to a technician who can quickly and usually fix your flooded laptop keyboard for free.

How to fix headphones if one doesn't work?

Who among us has not encountered a situation when the sound in one earphone begins to act up, and over time disappears altogether? Of course, the easiest way is to take them to a service center or buy a new pair. But first you should try to fix them yourself. How this is done is in the article.

How to fix a zipper if it comes apart?

The zipper is probably the most popular type of fastener today. It is used in clothing, shoes and bags. But such locks have an unpleasant feature - they come apart at the most inopportune moment. However, most often you can fix them yourself. The article will tell you how.

How to fix an outlet?

There are sockets in every house without exception. And of course, they are not insured against breakdowns. Calling a home repairman every time the sockets fail is not the best solution. After all, minor damage is easy to fix on your own. The article will tell you how to do this.

How to charge a tablet if the connector is broken?

Almost everyone has a tablet these days.

DIY keyboard repair

And one of the most common problems when using a gadget is a breakdown of the charging connector. In this case, it becomes impossible to use the device, because tablets are charged through it. How to charge a tablet if the connector is broken is in the article.

Do-it-yourself keyboard repair for stuck keyboard keys

How long does it take to repair a computer keyboard?

Computer keyboard repair does not contain complex technical manipulations and is very easy to learn and carry out at home, in this article
I will tell you in detail about all the breakdowns that occur among computer keyboards with step-by-step instructions on how to remove all breakdowns and malfunctions in this device.

How to repair a computer keyboard at home?

To repair your computer keyboard, you will need the following tools;

Cotton wool with cleaning solution.

Soldering iron and soldering kit.

Breakdowns and malfunctions that are often found in keyboards;

Buttons stick or are hard to press.

The buttons do not respond to pressing commands.

When connected, the keyboard is not detected.

When connected to the system unit there is a strange squeaking sound.

The wireless keyboard does not respond to any command.

If the buttons malfunction, if they stick, or they are hard to press, in this case it is necessary to completely disassemble the keyboard using cleaning agents and mechanisms in case of severe blockage, tweezers are used to remove severe blockages, and a vacuum cleaner is used to remove dust and dirt between the buttons themselves, if you You don't want to completely disassemble the keyboard.

If, when connecting the keyboard to the system unit, you find that it is not detected, then in this case you need to carefully examine the connection connector, and, if necessary, solder it if there is a defect in the cable itself.

The wireless keyboard runs on batteries; if it malfunctions, you must first replace them; if further necessary, you need to completely disassemble and completely clean the entire keyboard.

By following these easy procedures, you can easily repair your computer keyboard, while saving money on the purchase and repair of this keyboard.

In this article we will look at the problems that occur with keyboards, their repair and restoration - the complete and currently best service manual on the RuNet is provided. The focus is on repairing and restoring laptop keyboards, but everything described below can easily be applied to desktop keyboards.

Everyone knows that in any electronic device, as a rule, mechanical parts fail. Laptops are no exception - despite the fact that manufacturers around the world are constantly working to improve their reliability (and, consequently, service life), due to the small size of these devices, it is not possible to exclude the influence of various factors leading to the inoperability of certain devices. nodes

One of these risk areas for laptops is the keyboard. The unfortunate keys are subject to unbearable stress every day. Every day, the keyboard is exposed not only to mechanical stress (impacts on the keys during operation), but also dust, crumbs, and dog and cat hair. And under the most unfavorable circumstances, it turns out to be flooded with various kinds of liquids. Naturally, all this makes the life of a laptop keyboard extremely short.

Prevention

Here are the main symptoms indicating that your laptop keyboard is faulty:

the keyboard has changed its color
I started typing poorly, some keys don't work
after pressing the spacebar or any other key, this key does not return back

In a number of these problems, you can only get by with preventative work, but this is best done in a specialized service center. There are all the necessary tools, fluids and experience for this, because... inappropriate preventative actions can only worsen the current situation and often make the keyboard beyond repair.

The vast majority of laptops use a membrane keyboard. Conductors and contact pads are applied to the polymer film using vacuum deposition or chemical deposition. To increase mechanical strength, the contact pads can additionally be coated with a graphitized layer. Unfortunately, each manufacturer of laptop computers develops its own original topography for the layout of the film keyboard and replacing it from one model to another is impossible.

The main cause of a malfunction in the keyboard is the ingress of various liquids (Coca-Cola and Champagne are the most caustic), resulting in short-circuiting, oxidation or corroding of the conductive paths printed on the films. Cases of broken cable conductors and its breakage during independent attempts to disassemble the computer are still common. Almost any flooded keyboard can be repaired by restoring the damaged tracks with conductive glue.

How is prevention carried out?

First, you need to remove the keyboard. In principle, this procedure cannot be called too complicated. As a rule, to remove the keyboard, the clamps at the top of the keyboard are bent or pressed with a flat screwdriver, after which the top part is lifted, pulled up and away from itself, coming out of the lower grooves. The most important thing is to disconnect the flexible cable from the motherboard connector; it is very easy to damage a thin cable, but it is quite problematic to restore it. As a rule, the keyboard is connected to a flat connector, which consists of a fixed part into which the cable is installed, and a lock-seal plate.

Only after removing the keyboard can you determine the scale of the disaster, and understand whether it can be done simply with preventative measures or whether you will have to carry out repairs, and in the most unfavorable situation, install a new keyboard.

In the case of preventive maintenance, dirt and dust between the keys are first removed. There are special brushes for this, as well as cans of compressed air. Then you can start wiping the keys themselves and giving them their original shine. For this, there are special aerosols and liquids that remove dirt and add shine to plastic without damaging it.

Often crumbs, sugar granules, and food can be found under sticky flasks. It is better to try to remove them with a brush while simultaneously sucking them out with a vacuum cleaner.

Repair

Here are a number of typical cases when ordinary preventative maintenance will no longer help and more complex repairs are required.

1. Keys “stick” or are difficult to press

In the case when individual keys “stick” or are poorly pressed, unfortunately, simple prevention is not enough. Such defects occur when moisture gets into the mechanism, which over time mixes with dust and “cements” the moving part of the keyboard. To get rid of dirt, poorly functioning keys are dismantled.

After this, the mechanism is washed in a warm solution of a special cleaning agent. In some cases, it turns out that the silicone “blap” has worn through to holes; it is replaced with another one.

2. Spilled liquid on the laptop keyboard

Perhaps the biggest nuisance that can happen is liquid spilled on a laptop. If this happens, then under no circumstances place the computer on the battery to dry, as this will not help. Firstly, unplug the AC adapter and remove the battery, i.e. completely disconnect the device. And then take the laptop to a specialized service center as quickly as possible. If you are lucky and the liquid does not have time to corrode everything inside, you will get away with second-level preventive work (more serious). Otherwise, you risk having to replace or restore the keyboard, and sometimes even work on repairing the laptop motherboard.

To carry out the second level of prevention, it is necessary to dismantle the keyboard, rinse and dry thoroughly. Next, the film base is carefully removed from the keyboard; as a rule, it consists of several layers of film, onto which very thin current-carrying tracks are applied. It is important to note that when separating one film from another, you cannot tear it, since this will almost certainly tear the sputtered signal tracks. Each film must be washed in cold water and dried thoroughly. This procedure requires not only a lot of time, but also a lot of experience, because... The tracks are very thin and can easily be washed away during the process of working with films. Only after final drying can one assess how badly damaged the current-carrying paths are. If the tracks darkened and gaps appeared in them , then you can try to restore them with a special conductive varnish.

Unfortunately, after carrying out these steps, the keyboard is not always in working condition; this is due both to the composition of the liquids that were poured onto the keyboard and to how quickly the laptop arrived at the service center. If the second level of preventative work does not help, there is only one thing left - replacing the keyboard with a new one.

3. Broken or lost keys

Another problem that laptop owners face is broken or lost keys. In some cases, you can use a “donor” to fix this breakdown. Unfortunately, using “donor” keys is not always possible. This is also due to the fact that keys are broken in different ways, for example, if the mount itself is broken, then nothing can be done except change the keyboard for a new one. It’s the same with the fact that all laptops are different and finding a “donor” with an absolutely identical keyboard is extremely problematic. But meanwhile, such a possibility always remains.

If the “donor” could not be found, or its use is not possible, then there is only one thing left - replacing the keyboard with a new one.

Keyboard recovery

The vast majority of keyboards are made using film technology. Two films onto which contact pads and connecting conductors are applied by vacuum deposition. Between them, an insulating gasket is made from the same thin film with holes in the places where the contact pads are located. Under the keys there are rubber washers, which, when you press the button, compress the film sandwich and create electrical contact between certain contact pads. The conductive paths on the films are made of aluminum. When moisture gets in, aluminum oxidizes very quickly and the track breaks. In this case, both individual keys and entire groups of buttons stop working.

If the keyboard is flooded, you must first turn off the computer, disconnect the power and remove the battery. Then we wash the keyboard with cool water (not alcohol!), dry it, put it back and check. When washing, thin films of a flexible printed circuit board should not be rubbed - the conductive traces can easily be completely erased! Drying the keyboard should last at least a day. If, nevertheless, the keyboard partially or completely does not work, you will have to disassemble it and re-draw the rotten tracks. To work, we need conductive paint, glue or varnish. You don’t have to look for this liquid in specialized stores; its analogue for repairing rear window heating filaments can be bought at an auto parts store.

Most modern keyboards can be disassembled starting with the keys. The first step is to make a photocopy or photograph of the keyboard. Herself the key most often consists of two parts: the elevator and the platform keys, but on some keyboards you can add a spring-loaded element here. For removing keys, a dental hook or a tool of a similar shape from engineering kits is best suited. In principle, you can get by with a thin watch screwdriver. The key pad is connected with latches to the elevator; there are three to four connection points in total; it is worth noting that in the case of three there is one, and in the case of four there are two movable connections. The elevator itself is an X-shaped structure, which on the bottom side is attached to the key of the metal base of the keyboard, and on the other side - in the grooves of the platform. We are primarily interested in the fixed connection; it is necessary to insert a hook between these fixed connections into the gap between the platform and the elevator.

On which side are the fixed fasteners located? ? You can already find out by removing at least one key, but most often this is the lower part of the key. It’s better to start by lifting one key from one side and then from the opposite side in order to find out which half of the elevator is fixed on the keyboard backing and which one fits into the key grooves with latches. Typically, the keys are removed by prying them off from the top.

In the photographs you can see the elevator in a raised and lowered state. When elevated, the attachment points to the platform are clearly visible (the upper ones are movable, the lower ones are fixed).

We send plastic parts and rubber washers to soak in a bowl of warm water, to which a little washing powder or dishwashing detergent has been added.

Next you need to remove all the elevators. Since everything here is already visible, no difficulties should arise, there are also movable and fixed mounts (in the photo the top one is movable, the bottom ones are fixed), it’s easier and faster to remove, as a rule, from the fixed ones, but there are exceptions. On more or less modern keyboards, elevators have more degrees of freedom; they can not only fold (raise and fall), but also move relative to each other when folded . In this case, it is easier to extend the movable part of the elevator to the maximum (its fastening will go beyond the holding frame) and lift the elevator as a whole, and then release the stationary part from the “vice”.

Having removed all the elevators, it will be possible to remove from the aluminum substrate part of the keyboard with spring-loaded elements, and the polyethylene board with the tracks drawn on them. On fairly old keyboards, the disassembly method may be slightly different; an intermediate stage of removing the plastic edging will be added. In this case, you will need a hair dryer or a soldering iron with adjustable temperature. You need to melt the plastic on the back of the keyboard. When assembling, if possible, then melt the fasteners again to form caps; if not, then drop a quarter of a drop of super-torque or its analogues at the fastening points. Such keyboards most often do not have a layer with spring-loaded elements; these elements are made in the form of separate rubber caps.

You cannot use a soldering iron to repair damaged tracks. The film on which they are applied melts at the touch of a heated soldering iron, and to solder aluminum you will have to use a special flux. Therefore, to repair the keyboard, let’s put the soldering iron away and pay a visit to the nearest auto shop. There you will need to purchase an electrically conductive glue brand "Kontaktol" (Kontaktol-Auto, Kontaktol-Radio). This adhesive is used for quick repairs of car rear window heating filaments and for quick tracing of traces on small printed circuit boards. Other adhesives can be used, but they have greater resistance.

Now let's move on to the main part of the keyboard - flexible boards with drawn tracks. There are three polyethylene parts (sometimes 4), two with tracks and one empty to provide clearance. Two parts with tracks are most often connected to each other along one of the edges and form, as it were, one part, this part is simply folded in half (at the fold there are connecting tracks), but there are exceptions, for example, in the photographs there are three separate parts, just there contact pad for connection. As a rule, on old keyboards these three parts are not glued together (there are two or three spot gluing points), but on more or less recent ones this can be a problem. You can’t just disconnect it, just by pulling you can tear off the tracks where they intersect with the glue. Therefore, we arm ourselves with a hairdryer and a scalpel (or a utility knife), and slowly, starting from the corner of the keyboard (when I say keyboard, I mean the polyethylene part), we begin to separate the layers. The glue is most often blue. Don’t forget to warm up the glue well with a hairdryer before dividing any area. Don’t rush - even if you break a track somewhere, it can be restored later, but if a lot of tracks are torn off, restoring them will be a big problem. However, modern keyboards with non-glued layers are often found.

So, the layers are corroded. If you can see the remains of a liquid that was spilled, it is better to rinse this part of the keyboard again and dry it again. If there is obvious corrosion and adhered organic matter, wipe the layers with wet wipes for wiping LCD monitor screens. They are impregnated with a solution of isopropyl alcohol (but not alcohol itself - a very high concentration can corrode the coating) and are good at cleaning all kinds of organic contaminants.

Most often, damaged tracks can be seen with the naked eye, but you should still check them with a tester. Theoretically, all damaged areas need to be redrawn, but this is not always possible (the tracks are too close), and this is not always necessary, on a well-washed and dried keyboard, the corrosion process practically stops . All tracks should have a resistance close to 0 Ohm, most often several Ohms if the points being measured are far apart - not critical, but in theory, the tester should show short circuit . A damaged track may not ring at all or have quite a lot of resistance, in which case it is necessary to lay a track over the rotted one. If the track has rotted right up to the contact pad, then you will have to carefully clean the area directly next to the pad with a scalpel.

Practice has shown that all conductive adhesives differ in the specific linear resistance of the material. The glue introduces a resistance of 0.3 to 0.8 ohms per cm. The less, the better.

We find the damaged conductor. Usually, the metal on the current-carrying path in this place turns black or dissolves completely. Using a pencil eraser, you need to restore the metallic shine to the edges of the damaged area.

If such a damaged area is small, then you can immediately put a small drop of glue on the tip of a match or toothpick to restore the current-carrying path. But it’s better to do everything carefully. Along the damaged track on both sides I stick regular electrical tape. You can also use stationery tape, but it usually sticks strongly to the film and is subsequently more difficult to remove.

The glue is applied in a thin layer on the damaged area, so that the glue covers the undamaged areas of the contact track by 3-5 mm . After pre-drying for a few minutes, a second layer of glue is applied.

The actual drawing process can be seen in the photographs. After the glue dries, be sure to check the resistance. The adjacent paths are restored one by one: first we repair one path, then, after the glue on it has completely dried, we repair the adjacent path.

After finishing drawing and drying of the new tracks (for different adhesives from 15 minutes to 1.5-2 hours), it is worth assembling the polyethylene part, placing it on an aluminum pallet and placing the part with spring-loaded elements on top. In this form, carefully connect it, start the laptop and check whether all the keys work. To check, you can use a regular notepad or a special program Keyboard test.

If all the keys work normally, you can turn off the laptop, disconnect the keyboard and finish assembling it. Perhaps there is one nuance left with the installation of the keys, or rather with the key pads. After installing the elevators, platforms are installed; as a rule, the platform must be lowered onto the spring element in the center, and then press the platform strictly vertically down until it clicks.

Note: If after repair, when you turn on the laptop, it beeps and a key gets stuck, while pressing any other button removes the sticking, and all other keys work without problems, then There was some resistance left between some tracks - apparently they hadn't cleaned it well. If when you press one key a different symbol is displayed, then you have a short circuit. Study how the tracks of the key you pressed and the one whose symbol was displayed are connected.

Kontaktol glue in St. Petersburg was found in the following stores:

Mikronika. Novocherkassky, 51. 444-04-88
Radio components. Tramway Ave, 12. 377-17-25
Samodelkin tool. Tipanova, 5. 371-83-17; Slava, 52. 453-03-44.
Electronics Base. Bolshoy Prospekt, P.S., 100, letter A. 337-25-52

Partially used materials fromwww.azbooki.ru

A mouse is a device that helps the user work on a computer. If it breaks down, many users do not know how to switch from the keyboard to the required system icons. This situation leads to the end of the session and the search for service centers for repairing electronic equipment, or to the purchase of a new device. If you have such qualities as perseverance, attentiveness, and the ability to work with a tester and a soldering iron, then you can easily, based on the information provided, quickly determine the cause of the device failure and even repair it. Let's consider repairing a wireless mouse yourself.
Causes of failure.
Since the mouse is a reliable piece of equipment, in many cases the damage will be minor. It can happen due to:
1. Poor contact between the battery and the control board.
2. Failure of one of the electronic components.
3. Damage to the computer's USB port.
Identification of the cause of the malfunction and methods for its elimination.
To begin examining a broken device, you need to disconnect it from the power supply, remove the wireless communication module from the USB computer and remove the battery. To get to the control board in most models, it is enough to unscrew the fasteners located under the battery and use a flat-head screwdriver to disconnect the upper part of the case from the latches.

Visually or using a multimeter in the position of checking semiconductor devices, examine the plus and minus marks, connecting wires and soldering points for the presence of oxides and mechanical damage. Due to strong vibrations and mechanical stress, microcracks may occur at the junctions of elements with board tracks.

To identify them, you need to very carefully inspect and loosen the fastenings of the wires and electronic components of the board. When identifying suspicious or defective areas, they should be properly soldered.
If the measures described above do not restore the device’s functionality, check its resistance at the power terminals. It should be in the range of 400 - 600 Ohms. If the ohmmeter shows zero, then there is a short circuit in the electronic circuit; if it shows one, there is an open circuit. In these situations, it is necessary to check the electronic components. Any charred or swollen devices found must be replaced.
To check the health of the photodiode, connect the probe from the “V+” port to its positive input, and the probe from the “COM” port to the negative input. In this case, the multimeter is switched to diode testing mode. Turn on your phone's camera and point its lens at the photodiode. A serviceable element will light up in the displays.

If after all the above measures the mouse does not work, check the serviceability of the wireless module with a USB plug. Use the probe from the “COM” port to touch track 2, and with the other probe touch track 1. The readings should be 600 - 800 Ohms.

To check a computer's USB port, simply connect a working device, such as a keyboard or memory drive, to it. If the software responds after connecting, it means the port is working.
In other cases, when the failure could not be eliminated, the microcircuit needs to be replaced.

Enough has already been written about the tactile sensations, ease of use, and stylish appearance of the Logitech Illuminated K800 in various types of reviews. Let's talk about sad things. It so happened that beer was spilled on the keyboard. Quickly swiping and shaking out the liquid did not help - a decent amount of the drink got inside, but it continued to work. The next morning, the keyboard spontaneously began to produce meaningless combinations of characters, and then there was complete silence, only a couple of keys responded, and even those did not type what was shown on them. This case is not covered by warranty, so I decided to disassemble the keyboard. If anyone is interested in what's inside and how it can be opened, please see cat.

The keyboard is a fairly monolithic structure with the only visible screw on the battery compartment, unscrew it. Another screw will be visible inside, but you can leave it alone for now.
The next step is to separate the bottom cover. I had to tear off this lower part of the case at random; it was not clear where the latches were and how well the case was glued. I started with the places where the legs are - it’s easier to grab onto them, but still, you can’t do it without a screwdriver or other flat tool. It can be seen that one of the batteries is half covered with black film.

He acted at random and broke off several latches, but later it was refused that this was not critical, because... This cover is covered with layers of adhesive backing and they perfectly fix the cover with an incomplete set of latches. The photo shows stains and puddles from beer.

From the inside, the torn off bottom cover looks like this:

The places where the latches were are circled, in case it comes in handy:

Next, unscrew the 16 screws, which, among other internals, hold the upper part of the keyboard (the one with the logo). Pay attention to the black rectangle of thick film that covers half of one of the batteries. Its purpose is not entirely clear - it turns out that replacing batteries must necessarily be accompanied by tearing off the bottom cover of the keyboard, or you can cut it off with something sharp. But if you bend it, it turns out that there is another screw under the glued film; do not forget to unscrew it.

The thin transparent frame is secured with screws on the right and left, and to open it you need a smaller Phillips screwdriver than for the other screws.

Judging by the inscription, there is a proximity sensor at the bottom, which reacts when you bring your hands to the keyboard and turns on the backlight.
Let's get down to the tedious task of picking out the keys. The “scissors” mechanism holds the keys tightly; we hook the key from above and below and pull it up. I didn’t have enough experience and on some keys the latch that secures them to the mechanism itself broke off, which means that later they will pop out when pressed.

Don't forget where and what key is located.

For complete disassembly, it is necessary to disconnect the mechanism for securing each key. Firstly, for the purpose of washing, and secondly, without this there is no way to remove the layer with membranes and the layer with conductive tracks. We disconnect the mechanisms no less carefully than the keys.
Here is a video that shows how to detach the keys and the fastening mechanism (about the K800 from 3:22)

If, after all, the keys or mechanisms are damaged in the process, then eBay does not sell both of them separately (although I have not seen them with a Russian layout).
After this, you can disassemble the “sandwich” consisting of a layer with membranes, a layer with conductive tracks, a backlit layer and a metal plate to which the key mechanism is attached.

Let's make sure that the backlight works simply by turning on the keyboard. Let's check that the proximity sensor also reacts to the raising of hands.

Below the backlit layer is a metal plate on which everything rests.

I disassemble all the layers separately, they are spilled with beer, so each of them is sent under running water. I also wash the keys and their mechanisms so that nothing sticks together. I leave everything to dry until the next day.
The next day I checked the keyboard for functionality. The membranes are placed on a layer with contacts and all clicks are checked one by one. You can use a regular text editor or special programs. Everything is working! After checking, we assemble everything in the reverse order, paying attention to the keys and key mechanisms, they are quite fragile and the latches are easy to break off.

After the work done and two evenings spent disassembling and reassembling, I received a working keyboard and invaluable experience in disassembling and repairing Logitech keyboards.