DIY solenoid repair

In detail: DIY repair of the solenoid from a real master for the site my.housecope.com.

Quite often, motorists have the question of how to check, replace and repair the automatic transmission solenoids. This is due to the rather frequent failure. Also, quite often they just fail. This is known to every car owner who has a car with such a gearbox. Having the skills of such work, you can significantly save on maintenance of the machine. After all, almost all car services carry out automatic transmission repair work for substantial money, even in cases when the process takes a short time and does not require special skills. Knowing the features of checking and repairing this system, you can do everything yourself without resorting to the services of a car service.

It is necessary to think about checking and possible repairing solenoids when the following signs appear:

Pushing and hitting the box when moving;
When the automatic transmission malfunction light comes on;
Shifting gears with jerks.

In any of these cases, be sure to check the operation of the valve body.

It is necessary to start the check with computer diagnostics. If you see an error indicating a breakdown of the solenoids, then you can work with them further. For a more accurate diagnosis, we remove the part from the machine. For this, on the removed solenoid, the resistance is first checked. Depending on the model, the indicator can range from 10 to 25 ohms. More accurate indicators can be found in the technical documents for your car.

It is also imperative to check for jamming. To do this, a voltage of 12 V is applied to the valve contacts. The working solenoid, when connected, emits a soft click. If there are no sounds, then the problem is a blockage in the part. There is a compressed air test method. For this purpose, the solenoid is purged with air. A part normally closed when energized must allow air flow, normally open vice versa.

Installing new solenoids will not be difficult for you. The main thing is to do everything very carefully when working. Before replacing, determine your type of automatic transmission, according to this data, select the appropriate type of solenoid.

The replacement itself requires a minimum amount of work. The valve body is unscrewed from the box, after which it is necessary to squeeze it out of the clamps using a pry bar. The solenoids are removed from the unit and disconnected from the power supply. Further, new elements are installed and connected. The valve body is installed in its place; for this, be sure to use a new gasket. This will help prevent grease leaks.

Video (click to play).

If there are problems with gear shifting or extraneous noise in the gearbox, you should first of all pay attention to the serviceability of the solenoids. You can make special diagnostics that will help identify malfunctions at any car service center. Solenoids are electromechanical control valves that control the transmission. The ability to change gears in a car directly depends on their functioning. Possible solenoid malfunctions:

Clogging with carbon deposits and small debris from wear parts of the transmission;
Recoil spring tension;
Cracks on the body;
Falling winding resistance level due to breakage;
Wear of manifold channels.

After identifying the type of malfunction, you can proceed with the repair. The design of an automatic gearbox is quite complicated, and motorists who do not have the proper experience and do not understand how to repair cars are better off not doing any actions on their own. It's easier to go to a service station and use the services of professionals.As for experienced car owners, they can try to repair the automatic transmission solenoids on their own. It is worth remembering that not all breakdowns can be repaired. The solenoid can be cleaned of debris or the gaps can be soldered, and in other cases it is better to completely replace the failed part. To troubleshoot, you need to carry out the following operations:

Determine the type of malfunction and make sure that it can be repaired;
Remove the solenoid;
Carefully remove the coil from the body;
Find the break point;
Unsolder contacts;
Solder the gap and fill it with epoxy;
Insert the coil back into the body and check that it does not dangle;
Solder the contacts in place;
Thoroughly blow through the solenoid to clean it;
Replace the repaired part.

After repair, the solenoid should last a couple of years. If it is impossible to solder the wire at the break, you can simply rewind it. To find a service that conducts this type of work, you need to enter a specific search query on the Internet, for example, tire fitting 5 wheel Kazan.

Hello everyone. a month ago I bought myself a forika SG5 2002, turbo.

The ECO light started flashing occasionally. When it flashes, the car starts to move very slowly. The diagnostics said that there is a P0753 error. It's kind of like - “Damage to the electrical circuit of the solenoid switch A”.

We decided to look inside, drained the ATF, removed the bottom of the box. Visually wiring, contacts were okay. Then they decided to turn on the ignition, one solenoid began to twitch and oil was splashing from below it (a photo in the attached file). We thought that it was not working properly, since the rest of the solenoids worked fine. Someone faced such a situation, is it really faulty?

I also measured the resistance of the solenoid coil, it is equal to 7.8 ohms. It seems to me that this is very little resistance. Maybe someone knows what it should be there?

He began to repair this way, he began to neatly bend the edges of the cylinder in which the coil is located. I swayed it a little and decided to measure the resistance again, it became 3.8 ohms. It seems like 4 ohms is when the selenoid is whole. From this it follows that there is poor contact from the connector to the coil, if it is burnt, or something else.

People, what do you think about the work done, is it possible to further disassemble the solenoid? Maybe someone has already done this. Any comments would be welcome.

Having sent to retire a simple governor - a hydraulic valve with a mechanical principle of operation, the solenoid turned into a complex component of the automatic transmission valve body. Accordingly, repairing the automatic transmission solenoid with your own hands will require knowledge of electricians, mechanics and the gearbox device.

We need a set of tools (for flaring the solenoid) consisting of:

repair kit for automatic transmissions, for example, AISIN AW55-50 SN with spare bushings;
hammer;
calipers;
hex wrench;
carburetor cleaner;
flaring tool;
compressed air;
vice;
Press;
tray for small parts.

Repair kit for flaring the automatic transmission solenoid

We take the valve body and unscrew the solenoid turning bolt.
We remove the mounting bracket and take out the solenoid of interest to us.
Set the hydraulic unit to the side.
We measure the tightness of the spring with the lock nut using a vernier caliper.
Remove the counter pin from the solenoid and place it in the tray.
Unscrew the spring pre-tightening nut with a hex wrench. We act carefully so as not to damage the part.
They pulled out the spring. We put it in the tray.
We take out the solenoid stem, it does not always come out immediately, you need to shake it vigorously. We place in the tray.

We carry out the final procedures in the reverse order: we clean and press in the coil body, place the coil in the stem body (the risk of the connector should coincide with the slot), we roll the solenoid using a press and a ring from a repair kit, install the stem, spring and nut, tighten the nut to a depth, previously measured with a caliper, put on a corkscrew.

The solenoid is ready to be installed in the valve body. Successful repairs to you!

An automatic transmission of any formation is a rather complex mechanism, simply replete with all sorts of details. Some of them are only auxiliary in the operation of the device, while others are the real basis. It is in the category of the latter that the solenoids are responsible for shifting gears and controlling the modes of the box. We will talk in more detail about the principles of operation and the general concept of these automatic transmission elements today. Interesting? Then be sure to check out the article below.

The automatic transmission solenoid is a special device that is responsible for the movement of oil inside the valve body mechanism. It is controlled by an electronic automatic transmission control unit and, in fact, is a conventional electromechanical valve. It is solenoids that have become the most common "managers" of gear changes and operating modes in modern automatic transmissions. If in robotic and variator gearboxes it is possible to replace these units with something, then in hydraulic automatic transmissions they have become the basis of control, therefore they are unlikely to be supplanted within the next decades.

It is worth noting that the solenoid in the gearbox is far from one - there are many of them, which are often combined into whole blocks. Previously, the functions of controlling the movement of oil through the automatic transmission channels were assigned to mechanical valve mechanisms, however, the development of automotive electronics provoked the replacement of such devices with more convenient solenoids. To be more precise, the first solenoid was installed in the design of the machine only in the mid-80s in the United States, after which it became widespread in this area of application.

Again, any solenoid is an electromechanical device, which, frankly, is very simple in design. The main function of this mechanism is to shut off the oil supply through one or another automatic transmission channel by locking it with a special rod. The latter, by the way, is made of metal and simply slides into a conductive spiral (electricity flows in it constantly while the car's engine is running). An increase in current moves the rod to the end of the spiral, that is, it closes the oil supply channel, a decrease - to its beginning, respectively, increasing the supply of lubricant. The movement of the rod of any solenoid is organized using special mechanisms - locking and return springs.

All automatic transmission solenoids are assembled in its element called "valve body" (popularly - a solenoid block). The valve body, by the way, is a plate divided into numerous channels and has many sensors and valves in its design. This organization allows the machine to carry out the duties assigned to it, which are automatic gear shifting. The solenoids in this system play an important role and are controlled by the ECU, which sends them signals to open or close a specific valve body channel.

As it became clear from the previous paragraph of the article, it is difficult to imagine the automatic transmission control without solenoids. Depending on the principle on which these mechanisms work, it is customary to distinguish several generations of installations. Today, there are three main types of solenoids:

Over time, the design of the machine became more and more complex, therefore, the principles of operation of the automatic transmission solenoids became more complicated, because of which they underwent enhanced modernization. The main improvements concerned the transfer of additional functions to the valve, such as relieving pressure in a specific clutch block of the box or blocking the torque converter clutch.

The ideas of automotive engineers have made it possible to achieve similar goals. Now numerous types of solenoids are not only responsible for gear shifting, but also finely control the automatic transmission operating modes. Today, a standard machine has 6 types of solenoids in the design:

It is important to understand that for each pair of clutch (transmission) there is not one solenoid, but several of those noted above. Stable and trouble-free operation of the automatic transmission is possible only with the normal operation of all valves of the valve body, therefore, they must be treated with the proper level of responsibility.

A faulty solenoid is one of the main reasons for the incorrect operation and the transition of the automatic transmission to emergency mode. Despite the high reliability of modern valve body valves, in essence, these devices are consumables, therefore, they require periodic replacement. If the situation is not too advanced, the problem can be solved by a conventional oil change in the automatic transmission.... It is quite possible to change the solenoid with your own hands, but first of all it is important to diagnose its malfunction.

To check any valve of the hydroblock plate, you will have to carry out its "continuity". This is necessary for one simple reason: a faulty solenoid loses its normal resistance, to be more precise, it rises. How to check the solenoid? It is very simple, the valve diagnostics procedure is not complicated and consists in performing the following operations:

Remove the valve body from the box, which is often located on the bottom of the unit, less often on the side;

Disconnect the contacts of each solenoid from the corresponding connectors of the control unit;

Ring each valve. The rate of resistance on its tram lines is determined for each type on an individual basis. So, for example, for EV-1 solenoids, the resistance rate is in the range of 65-66 ohms (at 20 degrees Celsius). For other valves, the normal indicators, respectively, are their own.

Note! Modern boxes have self-diagnostic functions, therefore, to determine which solenoid is faulty, it is enough to connect to the car's on-board computer. If such a measure is not possible, then you will have to carry out diagnostics with the traditional "ringing" with your own hands, after which you will have to repair the required element of the assembly.Let's say a faulty valve has been identified - what is required next? Naturally, repair of the solenoid or a group of them. Unfortunately, it will not work to disassemble the valve, rinse it and put it back together; you will have to completely change the valve body element. Its cost is not very high, so you should not be afraid of the repair procedure. Often, replacing solenoids in an automatic transmission is carried out as follows:

The valve body is removed from the box;

All connectors are disconnected from the valve;

The solenoid mounts are unscrewed, and it is removed from the valve body;

After that, a new one is installed in place of the old valve, all connectors are attached to it;

Then the valve body is installed back to the checkpoint. The repair is over.

As you can see, there are no special difficulties in the arrangement of the machine solenoids and their repair. The material presented today will help to deal with both. We hope he was useful to you and gave answers to your questions. Good luck on the road and in auto repair!

Solenoids in automatic transmission: what is it, check and replacement

What are solenoids in automatic transmission for?

Where are the solenoids

Solenoid types

The main malfunctions of automatic transmission solenoids and their repair

How to check and replace solenoids

Automatic transmission solenoid - it is a solenoid valve regulator that performs the work of closing and opening the oil channel... Its work is controlled by an ECU that sends continuous electrical impulses at a specific frequency. The solenoid controls oil pressure on specific clutch ligaments by quickly changing gears or unlocking a hydraulic transformer. The automatic transmission solenoid is responsible for controlling the transmission modes.

The solenoid, or the solenoid valve, according to the general rules, is located in the valve body - the hydraulic valve plate.

In the valve body, it is inserted into the channel, where it is fastened to it using a bolt or a special pressure plate. At the other end, it is connected using a loop, or a wiring plug, to the automation control unit.

The automatic transmission solenoid is responsible for transmitting signals between the hydraulic and electrical systems. He combines them with his functions. And often this combination fails, which is determined by the computer.

There are at least 4 solenoids in the automatic transmission. Their number depends on the complexity of the circuit and the number of steps.

The ECU cable and cable are often the causes of solenoid breakage, therefore they are replaced as quickly as the solenoid.

The first solenoids designed specifically for automatic transmissions were on-off solenoids rather simple construction and with simple functions. Solenoids of this type worked according to the principle: "open" and "close". The rod, with the help of the current running through the winding, walked along the channel and performed the on / off function.

Another great type of solenoid is solenoid "solenoid valve" This is the perfect know-how for its time. It is actually a hydraulic valve. The developers gave him his own oil channel and a ball valve that opens and closes this oil channel. Easily detaches from the hydraulic system and power supply by simply unplugging the plug.

The first of the solenoids operated on / off. But, due to the development of the auto industry, in the early 90s, 3-way solenoids were created - new generation switches. In the on position, the ball valve opens the oil passage from channel 1 to channel 2, and in the off position, the passage from the 2nd to the 3rd. This development helped to combine the devices into one - to turn on and off the friction clutches.

Striving for excellence, designers in the mid-90s developed an even smarter type of solenoid. Solenoids - regulators, or "electric regulators", designed according to the valve principle. Depending on the type of pulse that comes from the computer, the internal curved section of the solenoid "opens" or "closes", that is, the current is supplied with certain interruptions and frequency.

Solenoids-regulators are ball, spool 3-way, 4-way, and even 5-way.

Ball valve solenoids have been developed - PWM solenoids... This is the first stage of development.

Later, quite rare solenoids appeared. VBS... They have low sensitivity to supply pressure variations and handle high line oil pressures well. They are also called spool valves, since they have a spool valve.

Linear (proportional) solenoids are designed in such a way that the most wearing element of the valve body plate, a coupling with holes through which the spool-plunger runs in this type of solenoid, is placed in the solenoid itself.

Linear solenoids are notable for the fact that they can be used to avoid replacing the entire hydraulic plate in the event of a breakdown of this element, and to restrict itself to replacing only one worn out solenoid. The hydraulic plate now lasts longer, and the problem with the wear of its channels has been eliminated.

This type of solenoids is quite capricious, and the resource of life, in comparison with linear solenoids, is shorter. Since, due to rapid wear due to low weight and increased pressure, the solenoid valve changes its opening level, and the computer needs accurate communication to correctly respond to such changes.

There are also solenoids according to their functional purpose:

These are solenoids EPC or Lpc (Line Pressure Control). It is one of the first in the hydraulic solenoid valve plate. This type of solenoid is the "ringleader". He single-handedly distributes oil to the rest of the solenoids and channels. With a 4-stage EPC, it wears out first.
Solenoid TCC... Performs the dirtiest job of all solenoid types. It affects the lock-engage torque converter clutch, increasing efficiency for Sport mode acceleration. It is often the weakest link in many valve bodies, since unfiltered and hot oil from the torque converter flows through this solenoid.
Shift solenoid. The so-called "shifter" is a solenoid switch. The simplest type of solenoids. Responsible for gear shifting.There are several such "shifters" in the hydraulic plate, and it is they who switch up and down in the box. They are designated as S1, S2, or A, B, and SL1 is a linear shifter.

The control solenoid is like a transistor in an electrical circuit, the solenoids can control the valves of the plate.

They direct and give a slight pressure to the valve body valve, which itself already applies pressure to the pistons and clutches.

There are 2 types of control solenoids:

- high-quality gear shift solenoid;
- oil cooling control solenoid.

Below we present the most common "diseases" of solenoids.

The reason for the breakdowns and "wedge" of the solenoids is that, due to low-quality oil, the solenoids are clogged with carbon deposits from paper, steel, bronze and aluminum dust, which is obtained from worn-out consumables and assemblies.

This problem is manifested by the fact that the solenoid valve works normally when the oil is cold, and when it is hot it slows down.

To correct this problem, it is recommended to rinse the solenoid, rinse in solvents, and clean with AC and solvent.

Leaks are a result of wear, breakage of parts such as plunger, manifold. In the presence of PWM solenoids in control, when one of them is weakened, the computer takes into account its wear and redirects part of the load to other solenoids.

This slightly extends the life of the aged part. But hot oil and the intensity of the voltage quickly wear out a weak solenoid, and then you have to change it.

The intensity of work, when redirecting pressure and some of the duties to other solenoids, wears out their channels and plungers. Thus, a continuous chain reaction is obtained.
The next problems and breakdowns are a decrease in the elasticity of the spring, cracks in the housing, a decrease in the resistance of the solenoid winding, and structural breakdowns.

The most common reason for failure of solenoids is wear of its parts: bushings, manifold, valve, plunger or ball.

The plunger is clogged with crumbs from worn parts and oil, it all starts with a problem with switching - it wedges, then the amount of carbon deposits increases, and bushings and valves fail.

But, nevertheless, due to all these innovations, fuel consumption has decreased, the dynamics and comfort of the car have increased, the entire automatic transmission mechanics began to work accurately, harmoniously and loaded. But such changes, in turn, led to rapid wear of parts and contamination of the oil by their particles.

Now you need to constantly change the oil, as it acquires the properties of sandpaper due to all these particles.

If you notice that it has become more difficult for you to switch speeds to certain gears, you notice unknown shavings in the pallet, your computer gives you distress signals - in search of reasons to turn directly to the solenoids.

It is easy enough to determine what kind of solenoid "wedges". Each solenoid is responsible for the gear group and torque converter control. It depends on the brand of your car and automatic transmission. For instance, if there are 4 solenoids in the box, then the first is responsible for switching gears 1-2, and, most likely, for 3-4 gears, the second for 2-3 gears, the third for the torque converter unit, the fourth is responsible for the operation of the brake band. If there is a problem with shifting from 2-3 gears, then, accordingly, this solenoid must be repaired or replaced.

If you feel jolts and bumps in the gearbox while driving, or the computer itself tells you about the problem (the code is displayed, the light is blinking, etc.), these cases indicate that an urgent need to check the valve body.

In these cases, you must check the part immediately. First of all, the solenoid is tested for resistance. A voltage of 12 V is applied to the valve contact. If the solenoid is working, then it will emit a click, but if there is none, then the problem is its clogging. For cleaning under voltage, blow through with compressed air - the solenoid must pass it through. If not, it needs to be replaced.

DIY repair of the solenoid is possible, but only in cases where the part itself is collapsible. Modern parts, for the most part, are now produced not collapsible. For such parts, the only repair option is purging or ultrasound. If the part is collapsible, then you can change the winding, rinse all parts in gasoline, dry and assemble. After these steps, we recommend checking the solenoid for operability.

If you have failed to repair the solenoid, then replacing it in the automatic transmission is not difficult, the main thing is to do everything carefully and carefully. Before you start work, you need to determine the type of your automatic transmission, and, based on these data, choose a suitable solenoid. We detach the valve body from the box, disconnect the solenoid from the power supply and remove it from the unit. Next, we install new parts. We install the valve body in its rightful place, not forgetting about the new gasket.

How to check, replace and repair automatic transmission solenoids? Brief manual

How to check, replace and repair automatic transmission solenoids? To answer this question correctly, you need to know the structural features of this device. The automatic transmission solenoid is a rod in a copper winding. When electricity is applied to it, the rod moves, opening the valve. Through which oil passes, changing gears. There are 2 types of solenoid according to the way of operation:

Normally open. This solenoid opens at rest. When current is applied, it closes.

There are also multichannel solenoids, the principle of their operation is no different. These parts are calculated for an average of 300,000-400,000 switching cycles. It depends a lot on the box. In some cases, they can fail much earlier.

Repair of any automatic transmission from 1 day

CVTs, DSG, torque converters, new and remanufactured automatic transmissions, spare parts

# 1 Post Evgeniy Zh 09-03-08, 09:31

# 2 Post ahor75 06-03-07, 08:31

# 3 Post Dyukanm 06-03-07, 08:31

# 4 Post Evgeniy Zh 09-03-08, 09:31

# 5 Post arsas 09 Feb 2012 11:12 am

# 6 Post _s-s_ 09-03-2012 01:37 PM

# 7 Post Evgeniy Zh Fri Nov 09, 2012 2:02 pm

# 8 Post vitalio Fri Nov 09, 2012 2:03 pm

# 9 Post Baberr Fri Nov 09, 2012 3:09 pm

# 10 Post unforgivable503 Fri Nov 09, 2012 4:09 pm

# 11 Message Baberr 09-03-2012 4:45 pm

# 12 Post ZAP 09-03-2012 4:46 pm

# 13 Message unforgivable503 Fri Nov 09, 2012 5:06 pm

80-90 percent of the price of a new part)

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AGGREGATKA is a federal network of technical centers, the main specialization of which is the repair and maintenance of automatic transmissions of all types, including robotic transmissions with double clutch, CVT transmissions and classic hydromechanical automatic transmissions

Toyota Crown Club / Crown Majesta

NetRino "22 Nov 2006

Dear All!
maybe someone will use my experience in repairing the automatic transmission solenoid.

After that, it must be blown out, wiped thoroughly and can be put back in the box.
From experience - I've been driving for a month after such a repair, and a new solenoid has already arrived by order (it will remain in stock)
I expect that a year or 2 will work

P.S. even if the wire in the coil is broken off completely or damage somewhere inside in any radio workshop you can rewind such a coil, the main thing in the solenoid is probably a valve that must hold a lot of pressure, and electricity can be treated.

Login_Pitersky "22 Nov 2006

NetRino "22 Nov 2006

OLEG_55 "22 Nov 2006

Young man!

Holo November 29, 2006

Damn, super, sorry I don’t have a garage with a pit ((((where the car could have painted for a couple of days, otherwise I would have done

although I have a couple of solenoids that do not suit me in size, you can practice on them, if it works out, then Mona try it on her own,

how I gouged the test, I will try to post pictures

Initially, gearboxes were equipped with the so-called Governor... It is a primitive hydraulic valve that worked on a mechanical principle. Today, on modern automatic transmissions, solenoids are used exclusively, which are controlled by the automatics. The advantages of using a solenoid are increased reliability, the ability to fine-tune and fine-tune the operation of an automatic transmission.

Content :

The solenoid design consists of a special magnetic bar with a copper winding inside. A direct current is fed through the winding, which pushes the magnetic bar in the direction of oil movement. When the voltage changes, the magnetic bar moves in the opposite direction. Despite the apparent complexity, this design is simple and easy to operate. In modern automatic transmissions, the solenoids move not only under the influence of a change in the direction of the current, but also due to a special return spring. This ensures increased reliability of the device and the possibility of correct functioning of the solenoid in case of problems with the power supply.

Solenoids are located in special channels of the valve body, through which the oily liquid moves. When the channel is open, the oil circulates freely through the channel and is directed to the moving parts of the box or to the oil receiver for subsequent cooling.

The solenoids are controlled by a computer, which is connected to the electric valves using a special loop. It should be noted that the loops, through which control signals are transmitted to the electric valves, are a weak point in the design and often fail. That is why, in case of problems in the operation of the solenoids, first of all, in the repair shops, they check the operability of the loop.

Valve bodies in most modern gearbox models are located at the bottom of the gearbox. Only in some transmissions is the valve body located on the left or right side. The bottom arrangement of the electric valves makes the repair work much easier. Replacing solenoids in automatic transmission can be produced in specialized service centers. Note that this work is done without removing the automatic transmission from the car.

Several types of solenoids are used in modern automatic boxes. For the first time, these electric valves were used by American car manufacturers back in the eighties of the last century. In fact, they were a specially opening and closing valve, which stood in the channel through which the oil pump drives the working fluid into the system. In fact, such solenoids had two positions: Open and Closed.

These electric valves have been replaced by solenoids, which were developed by the Swedish car manufacturer Volvo. Such designs had a special pushing core and a built-in metal ball valve. The valve made it possible to open or close the oil channel. Despite its efficiency, such a design has not received proper distribution. The problem was a complex design that often broke down.

Soon, special three-channel solenoids became widely used, which made it possible to easily regulate the pressures of the system and direct the oil to the moving elements or to the cooling system. The elaborate design of such three-channel solenoids was distinguished by reliability and durability.

In the mid-nineties, intelligent solenoids appeared that made it possible to optimally control the operation of the valve body. Solenoids-regulators became very popular, which used the valve principle and made it possible not only to close or open the channel for oil movement, but also to open by a certain amount, which made it possible to regulate the volume of pumped oil. The valve was opened along the cross-section in the rod, and the control was carried out from a central computer, which directed a pulse current to the magnetic core of the solenoid. Simultaneously with the change in the principle of operation, engineers of the world's leading automakers have modernized the design of the electric valves, which made it possible to make three, four and five-channel solenoids. The design itself was significantly simplified, which in turn had a positive effect on reliability. The valve body began to serve much longer, and its failures due to breakdowns of the solenoids became a rarity. The problem of wear of the hydraulic plate channels, which was one of the main causes of breakdowns in automatic transmissions, was practically completely solved.

Solenoids are usually classified according to their purpose. The most widespread are two types of electric valves - EPC and TCC. The former are responsible for the operation of the main supply channel and the channel through which the oil flows into the oil sump. The TCC solenoid is responsible for blocking the torque converter and provides the ability to increase the volume of oil supply to the gearbox.

The solenoids currently used in automatic transmissions are reliable and durable. However, it would be wrong to argue that this element is completely devoid of any problems and breakdowns. Like any other mechanical element, the solenoid can break and fail. Let's describe the most common breakdowns and their causes.

So, for example, quite often there is an increase in oil deposits and the smallest dust on the metal core. As a result, the core does not extend into the stem even when the required electrical signal is received. At the operating temperature of the oil in the gearbox, the solenoid can wedge, and the car will give an error in the operation of the gearbox. This problem can be eliminated by flushing the solenoids in special solvents. Solenoid block can be cleaned with ultrasound. The latter is carried out without dismantling the solenoids from the gearbox. We recommend performing ultrasonic cleaning of the solenoids every 50 thousand kilometers.

This is what the solenoid block looks like.

With a car mileage of 250 - 300 thousand kilometers or with the maximum active operation of the vehicle, wear of the inlet and plunger parts may be noted. All this leads to the appearance of oil leaks. Problems appear in the operation of the gearbox cooling and lubrication system. In this case, the repair of worn out solenoids consists in examining them for new spare parts.

A common reason for failure of solenoids is the use of low-quality oil or the absence of an oil change in the box. Working fluid with wear debris gradually wedges the magnetic core on a hot or cold machine. It must be remembered that it is extremely difficult to diagnose such a breakdown. That is why we recommend changing the oil in an automatic transmission in accordance with the manufacturer's recommendations. Use only quality oils.

Video (click to play).

Specialized workshops will tell you how to check solenoids and, if necessary, carry out a replacement. The cost of these items is not too high. However, you should understand that a gearbox may contain several of these elements. And if the electric valves fail, all solenoids are replaced.That is why the repair of this element can be quite expensive. Remember that the use of quality oil is the key to the long life of the solenoids.