The box went into emergency mode. Automatic transmission emergency mode - reasons and solutions. Influence on vehicle movement

Let's start with the fact that today there are several types of automatic transmissions:, and. At the same time, for each type of gearbox, various malfunctions are characteristic, and quite often and regardless of the type of gearbox, the automatic machine "rises" into emergency mode.

In this article we will look at the classic automatic transmission with (hydromechanical automatic transmission), what is the emergency mode for an automatic machine of this type, and also why the automatic transmission goes into an "accident".

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Automatic transmission emergency mode: what is it

So, the transition of the gearbox to emergency mode occurs if there is a breakdown or malfunction of the unit. In other words, turning on the emergency mode on the machine signals the occurrence of certain malfunctions.

At the same time, notifications or warning lamps check AT, HOLD, check engine, etc. light up on the instrument panel. If the automatic transmission "got" into an accident, the car stops dynamically accelerating, the sharp response to pressing the gas pedal disappears, the gears are not switched in D mode, etc. The fact is that in this mode the car starts off and moves only in third gear.

At the same time, the emergency mode itself can be considered protective, since its inclusion allows you to prevent a number of more serious damage to the automatic transmission. Even the emergency mode of the automatic transmission retains the ability to continue driving on its own to the nearest service station.

In other words, you cannot constantly drive in the automatic transmission emergency mode, but you can get to the car service without either a tow truck. Now let's look at why and when the automatic transmission emergency mode turns on, the reasons for its activation, as well as options and ways to solve the problem.

Automatic transmission gets into emergency mode: reasons

Let's start with the fact that modern automatic transmissions are quite a complex unit. At the same time, as practice shows, there are several main reasons why the automatic transmission "falls" in an accident.

First of all, a low or high level of ATF in the box can lead to malfunctions, as a result of which the emergency mode is activated by the command of the automatic transmission ECU.

A decrease in level can occur as a result of leaks, while an excess occurs often due to errors during maintenance of the box. For example, overflowing fluid in an automatic transmission leads to foaming, and a lack of oil leads to starvation.

The result is a decrease in pressure and deterioration of lubrication, rubbing surfaces at the points of contact wear out heavily. The electronics fixes deviations from the norm, the emergency mode is turned on, an error is recorded in the ECU by the box.

For this reason, if the box goes into emergency mode, it is necessary. It is also recommended to carry out a self-diagnosis of the automatic transmission (with such an opportunity and the presence of skills to carry out this operation).

Another cause can be malfunctions associated with the operation of hydraulic devices, as well as problems with the mechanics. For example, the automatic transmission emergency mode can turn on if the automatic transmission case is damaged, slipping, worn out, skidding or "burned", there are problems with the gas turbine engine, etc.

In this case, it is necessary to carry out an in-depth diagnosis of the automatic transmission. The check begins with computer diagnostics, but such a scan does not always allow you to get a clear idea of the nature and cause of the malfunction.

In this case, it may be necessary to dismantle the gearbox pallet in order to inspect for the presence of dirt, friction dust, metal shavings. In some cases, for troubleshooting, it will also be necessary to completely remove the automatic transmission and disassemble the unit in order to assess the degree of wear and the condition of individual elements.

The third reason for the transition of the machine to emergency mode is problems with the electronic control system of the automatic transmission. In this case, the symptoms can be different, the malfunction can be "floating" or persist permanently.

For example, it works fine on a cold box, but after warming up, the automatic transmission immediately goes into emergency mode. In such a situation, the culprit is often the temperature sensor, which requires replacement.

If the gearbox "falls" into emergency mode unexpectedly, that is, regardless of various factors and conditions, then the cause may be trivial damage to the electrical wiring, problems with contacts, etc. In this case, an experienced diagnostician checks the wiring and connections.

We also add that if the gearbox unexpectedly goes into emergency mode, and such a transition does not occur during gear changes, then the reason may be sensors (camshaft sensor, etc.). In this case, you need a comprehensive one.

Also, often problems with the automatic transmission arise when the driver moves the selector to position D or at the time of switching from 1st to 2nd gear. At this time, a blow is heard in the box, then the automatic transmission emergency mode is activated. In this situation, there is a high probability of damage to the shaft rotation sensors.

It should be remembered that the contacts of the sensors can oxidize or break off, thin wiring often breaks, loops wear out, etc. As a result, the connection with is lost. This is also one of the answers to the question of why the automatic transmission went into emergency mode.

To diagnose automatic transmission in emergency mode, it is better to read errors using a diagnostic scanner, since automatic transmission self-diagnosis is not always able to identify a problem. If the diagnostics give no results, then the breakdown should be looked for manually (by checking the sensors, "ringing" the circuits, etc.).

If the automatic transmission is in emergency mode all the time, and restarting the engine or resetting errors does not help, and the sensors and wiring are in order, then the possibility of problems with the transmission ECU should not be ruled out. In this case, they often resort to the method of replacing the block with a known worker for verification purposes.

A common cause of automatic transmission failure is contamination / damage to the channels, the appearance of scoring in the valve plate, and malfunctioning of the solenoids. In this case, the machine operates in emergency mode. The reason is the increased sensitivity to the quality of the oil in the automatic transmission and the pressure of the fluid.

To avoid such a breakdown, it is necessary in a timely manner. You also need to use only such ATF fluid that the manufacturer allows for use in a particular type of automatic transmission.

Remember, mixing transmission fluids from different manufacturers can lead to the additive packages reacting, as a result, the properties of the oil will change and the automatic transmission will malfunction.

It turns out that if the automatic transmission has switched to emergency mode, the oil level is normal, but its color, smell, viscosity and general condition are in doubt, then you should diagnose the box and be prepared, at least,

What is the bottom line

As you can see, there are a lot of reasons why the automatic gearbox emergency mode is turned on. At the same time, even rare activations of this mode, which are eliminated by restarting the internal combustion engine, indicate that the problem with the machine already exists and with a high degree of probability will only progress.

As for the errors and failures themselves, prolonged driving in a car in which the box went into emergency mode is not allowed. In other words, in this mode, you can only get to the car service, while avoiding the load on the automatic transmission.

Let us remind you once again that until the breakdown or malfunction is eliminated, the normal operation of a car with an automatic gearbox in emergency mode is prohibited! Moreover, if the automatic transmission has already "gone" into an accident, but when driving, extraneous sounds are heard during the operation of the machine (grinding, hum, crunching, bumps), then it is better to refuse to drive to the service on its own.

The optimal rhenium in such a situation would be to call a tow truck, since towing a car with a faulty automatic machine without hanging the driving wheels can lead to even more serious consequences for the automatic transmission, which is already faulty by itself and went into the "accident" mode.

Valve body channels wear

The work on shifting gears in the automatic transmission is carried out with the help of ATF circulating under the pressure generated by the pump. Its distribution to the mechanical units of the box takes place in the valve body using a system of solenoid valves, through special channels to create high pressure.

Like any working fluid, ATF loses its properties over time, becoming contaminated with wear products - metal dust and microchips. The chemical structure of the liquid and its color change, and a characteristic odor appears.

If the ATF is not replaced in time, the microparticles floating in it, working as an abrasive, leave scratches and scuffs on the surface of the valve body channels. The diameter of the channels affects the pressure, and any change in their inner surface leads to disturbances in the movement of fluid inside the valve body. This leads to a violation of the operation algorithm of the electronic control unit (automatic transmission ECU), which controls the distribution of flows.

Valve body malfunction is determined by some signs:

If the oil in the automatic transmission is not changed on time, unpleasant consequences can happen.

the appearance of grinding sounds when changing gear;
jerks and blows when moving the selector knob;
jerks at idle;
the engine may stall when the selector is shifted to driving mode.

Repair of the box unit consists in removing, cleaning and purging the channels. On different brands and models, the repair has its own characteristics, in some cases it is required to dismantle the automatic transmission.

In order to gain access to the valve body, drain the transmission fluid and remove the pan. After that, the electrical connectors are disconnected, the valve body is unscrewed and dismantled, which consists of several metal plates connected by bolts. It should be disassembled carefully, without losing the technological springs.

During operation, dirt and friction products are deposited on the channel walls. You can clean them with gasoline, but it is better to use liquid to clean the carburetors. The cleaned plates are carefully examined. With severe wear of parts, the entire unit must be replaced.

All procedures should be carried out in a clean room: during assembly, dust and small debris should not get inside. In the repaired box, the oil filter is changed, and fresh ATF is poured inside.

Changing the transmission oil level

This is another common reason why the automatic transmission goes into emergency mode. Even if the quality of ATF is maintained, an excess or insufficient amount of it negatively affects the operation of the transmission. When overflowing, the liquid foams, which changes its density and initial properties (cooling and lubricating), pressure drops. When underfilling, the necessary pressure is also lost, and the liquid is more quickly contaminated with wear products and overheating.

To bring the transmission fluid level back to normal, it is necessary to drain the excess or, conversely, top up. In this case, only ATF of the brand that is already filled in the box should be used. With a complete oil change, it is necessary to remove the automatic transmission pan to remove all residues.

When changing the oil in the automatic transmission, remove the sump to remove all residues.

If for several days the liquid level is stable at one mark, this indicates that there is no leak in the circulation system. If the level drops, you must carefully inspect all joints and gaskets for the presence of greasy streaks. In suspicious places, tighten the clamps, replace the gaskets or seal the connection.

Malfunctions of mechanics and electronic control system

Failure to comply with the timing of replacing the transmission fluid leads to mechanical damage to the automatic transmission. At low pressure, the friction of the clutches on the disc is maximum, the surface structure is disturbed, they "burn", and the gaps increase. This causes the box to kick. Car owners should pay attention to any oddities and changes in the car's behavior:

the car does not go forward, while the reverse gear is maintained;
no reverse;
the movement of the car in "neutral";
kickdown does not work;
"Kicks" when switching gears while driving, increased vibration;
the engine stalls or troit when driving mode is turned on.

Normal wear and tear combined with untimely maintenance can lead to mechanical failures:

jamming of valve body valves;
wear of friction discs and brake bands;
destruction or wear of the cuffs in the pistons of the friction disc packs;
wear of the splines in the clutch drum housing;
wear of the splines in the hub of the torque converter turbine and slipping of the gearbox shaft;
wear of the splines on the stator shaft of the torque converter;
deformation or destruction of blades on the reactor or turbine wheel of the torque converter.

Hydromechanical gearbox.

The mechanical part of the transmission is controlled by a programmable ECU by transmitting signals through the loops of wires. Failure of the unit itself is possible due to the effects of an aggressive environment, since over time the tightness of the protective casing of the electronic board can be violated. The readings are taken by sensors, which sometimes fail.

Signal transmission can also be interrupted due to corrosion in the connector strips or when the electrical wiring is broken (and corrosion also happens inside the insulation), the integrity of which can be checked using a tester, having at hand the electrical or wiring diagram of the car. Having found an open circuit, they solder the ends of the open circuit and insulate the junction well so that moisture and dirt do not get on the metal of the wire.

Oxidized connector pins must be thoroughly cleaned to remove accumulated dirt and corrosion. Pay attention to the condition of the insulating gaskets. If it is not possible to replace them, a silicone sealant should be used.

What to do if the automatic transmission goes into emergency mode

Influence on vehicle movement

When the emergency mode is turned on, only one high-speed gear remains operational. The car does not lose speed, and many people have a question whether it is possible to drive in such a situation. Using a car will make the problem worse.

When the box goes into emergency mode, you must slowly, at a speed of no more than 40 km / h, get to the service or to the parking lot if you plan to carry out diagnostics yourself. For this, the manufacturers have provided for the possibility of working in emergency mode of one gear.

You need to start the check by determining the error code - cars with electronic control and monitoring systems have a self-test function. By connecting the autoscanner to the dedicated connector of the electronic unit, you can display the required readings on the display.

The scan result and the table of error codes will tell you in which direction to search further. The fault lies either in the electrical part and control, or in the mechanical or in the solenoid valve system. Next, you need to decide whether to continue the diagnosis yourself.

When the malfunction is detected and eliminated, it is necessary to reset the error in the ECU memory, otherwise, during normal operation of the transmission units, the “check” on the panel will mislead the driver.

An automatic transmission goes into a "crash" if the self-diagnosis system detects a malfunction, which may damage the gearbox during further movement. Consider why the automatic transmission emergency mode is dangerous, how to independently read the breakdown codes, reset the error and find the reason for its occurrence.

The automatic transmission emergency mode is intended only to get to the nearest safe stop and call a tow truck. Nevertheless, if the cause of the malfunction is not an insufficient oil level, there is no grinding sound from the box, then in most cases you can get to the nearest service station on your own.

What to do if the machine goes into an accident?

In the event of a valve body solenoid malfunction, wiring problems, a short movement should not turn into sad consequences, since the automatic transmission ECU selects the safest operating mode. Emergency mode means that the car is only moving at one of the speeds. If the automatic transmission got into an accident and blocked the second or third gear, adhere to the following algorithm of actions:

stop and check the oil level in the automatic transmission. If the transmission is not designed with a dipstick, look under the vehicle. The escaping transmission fluid is red, the characteristic smell of burnt oil suggests that you should not go further;
wiggle the wiring harness going to the automatic transmission. If the reason is poor contact of the engine compartment wiring, with the proper combination of circumstances, you will be able to temporarily remove the box from emergency mode;
turn off the engine, turn off the ignition for 1-2 minutes. If it does not help, disconnect the negative terminal of the battery for 2-3 minutes. On some cars, such manipulations really allow you to remove the emergency mode;
if the oil level is normal, continue driving to a safe stop or the nearest service station. In this case, you need to drive as carefully as possible. Do not push the pedal to the floor, driving the engine speed into the red zone.

Possible causes of the malfunction

Going beyond the operating temperature, in other words - overheating.
Insufficient ATF level, resulting in a decrease in oil pressure in the valve body. Often, a breakdown does not come with lightning speed and begins to manifest itself with a belated gearshift, jerks, blows when switching.
Malfunction. For an accurate selection of the moment of gear shifting, effective acceleration and fuel economy, the electronic control unit of the automatic transmission is based on the readings of either MAP or DPDZ. Incorrect operation of the sensors ignites the Check Engine on the dashboard, but it can also cause jolts, impacts and the automatic transmission going into emergency mode.

Where should you start diagnostics?

Only the earliest models dispensed with electronics. All other units, depending on the model and year of production of the automatic transmission, have an electronic "brain" and a self-diagnosis system. If the automatic transmission on your car got into an "accident", you should start with computer diagnostics. You will need a device to connect to the diagnostic socket and the corresponding software to read the information. After reading the current trouble codes, look for their decryptions on the Internet in order to better understand the direction of further searches. The most common causes of automatic transmission emergency mode:

incorrect gear ratio of individual gears;
malfunctions in the electrical circuit of the solenoid valves;
mismatch of the speed of the input and output shaft of the gearbox.

In case of an error on the solenoid valves, do not rush to disassemble the automatic transmission. It is necessary to diagnose the wiring and ECU of the automatic box. If you know, then easily check the resistance of the wires of the shaft rotation sensor. You need to remove the connectors from the box body, as well as the connector of the automatic transmission control unit. Check the wires not only for open circuit, short circuit to "-", "+", but also for a short circuit with each other. This is quite likely in the event of chafing or melting of the insulation. Also, be sure to check if power is coming to the connector of the control unit and if there is a reliable ground. The location of the control units, the pinout of the connectors and the colors of the wires can be found in the manual for the repair and operation of the car.

In the video, Ivan Saychenko shows how to properly check the wiring if the automatic transmission is in emergency mode.

Visual inspection and soldering of contacts

When looking for the cause of the emergency mode of an automatic transmission, pay attention not only to the wiring harnesses where they touch the body, but also to the power connectors themselves. Sometimes, due to the effects of corrosion, careless removal / installation, the pins of the connectors simply break off. The automatic transmission can go into emergency mode even if there are oxides on the contacts.

On many Audi, Mercedes, the ECU of the machine is located under the front seat, where moisture often gets. Before disassembling the automatic transmission, it will be useful to pull out the control unit board. Even if there are no oxides on it, we recommend that you make sure that there are no microcracks in the soldering points, and, if necessary, solder the main contacts.

We recommend disassembling the box for troubleshooting the hydraulic unit, checking solenoids, clutch packs only after a complete diagnosis of electrical circuits and easily accessible elements.

Old automatic transmissions were very reliable mechanisms. Initially, they did not have any complex electronics and control systems. The gears were simply shifted alternately, depending on the readings of a pair of sensors, there was no control system, sports modes, and so on. But according to modern trends to improve fuel efficiency and vehicle efficiency, more and more changes have been made to them. Since the end of the 80s, automatic transmissions were gradually transferred to electronic control, and in the mid-90s, electronic control units (in fact, computers) began to be installed on them, an economy mode, sports and a mode for winter appeared, the steps became more and more.

The complication and fine tuning of systems made modern automatic transmissions very reliable.

In the 2000s, automatic transmissions came to a modern form - they began to work in tandem with the engine, controlled by one or two electronic control units, the control itself was transferred to the hydraulic block of the box. The complication and fine tuning of systems made modern automatic transmissions much less reliable.

Like any computer, the electronic control unit can make a mistake, "glitch". In this case, the emergency mode will disappear after stopping and starting the engine. In some cases, it helps to reset the terminal from the battery. It is not always possible to remove the error in this way. If this did not happen, then it’s time to go for diagnostics.

In emergency mode, the car loses its dynamics, the gear does not turn on, slowly picks up speed, the control lamps are on, indicating that something is wrong with the automatic transmission.

You cannot drive in emergency mode - it exists only to drive several kilometers to the service. Usually, in an automatic transmission in emergency mode, only the third speed is turned on, at which starting from a place and driving takes place. It is not recommended to accelerate over 60 in this gear, the engine and gearbox will be very hot. Getting under way in third gear is also difficult, especially in winter.

When the "HOLD" lamp blinks, the automatic transmission goes into Emergency Mode

If the activation of the emergency mode is accompanied by the appearance of any non-passing extraneous noise from the box, it is better to use a tow truck. Serious car services that repair automatic transmissions provide a tow truck free of charge.

If a breakdown occurs on the highway, where it is problematic to find a car service, then you can take a chance and try to drive in an emergency box. Only here the result of this may be different - from "it did not get any worse" to the purchase of a new automatic transmission. You should ride, without accelerating more than 80 km / h, smoothly accelerating and braking, trying once again not to sink the gas pedal to the floor.

Reasons for leaving the box in emergency mode

Modern automatic transmissions are complex mechanisms. Unlike their predecessors, modern copies are closely connected to the engine, controlled by electronics and have a lot of sensors and protections.

The first and most common reason for the transition of the box to the emergency mode of the automatic transmission is an abnormal oil level. It occurs due to a leak in the automatic transmission, oil overflow or abnormal operation of the valve body. If we are not talking about the valve body, it is easy to fix. Leaks in the automatic transmission can be both mild and serious - for example, damage to the automatic transmission case or the gasket between the engine and the automatic transmission is out of order.

Emergency mode occurs due to a leak in the automatic transmission

Such repairs will not be cheap. In mild cases, some gasket or seal is usually responsible for the oil leak.

Low oil level in the box is very dangerous. Some gearbox assemblies cease to be lubricated normally and begin to wear out, contaminating the entire automatic transmission with their fragments. Other units begin to overheat and this also does not affect them in the best way. As a result, a chain reaction occurs - the weakest and most distant parts break, then all the rest. High oil levels are also dangerous. At best, excess oil will be thrown out through the breather. At worst, it will foam and simply lose its properties, bringing the automatic transmission to the same picture as with oil starvation.

This can also include the operation of the automatic transmission on "non-native" oil. Some automatic transmissions are so optimized and tuned that they simply cannot operate on oil with slightly different characteristics.

The second reason is that the self-diagnosis system has identified problems with the hydraulic or mechanical part of the automatic transmission. Most often it is the wear of the clutches. The electronic diagnostic system will be able to correctly indicate a breakdown only in some cases. In any case, you will need to remove the box and inspect its insides for wear and damage.

One of the reasons for the emergency mode of the automatic transmission is problems with the hydraulic part.

Worn out clutches will quickly make the oil burn, it will saturate the rest of the clutches and at one point the automatic transmission will "stop" completely until it is pumped out. Broken gear teeth or frayed metal parts will quickly disable neighboring ones, and where it was necessary to change one small part, the entire gear will have to be changed.

The third reason is a malfunction of the electronic control unit, wiring or sensors. And this is the real scourge of modern automatic transmissions. Most often it is a bad contact of one of the loops. Most of the contacts in automatic transmissions are very small and thin wires, tracks less than a millimeter thick and loops thinner than a sheet of paper. Damaging such wiring is as easy as shelling pears. Such a small nuisance, in addition to the emergency mode, can give not frail symptoms in the form of kicks, jerks, slippage and loss of gears. The transition to emergency mode in this case is chaotic. The automatic transmission can safely drive for a week, and on weekends it goes into emergency mode on every bump.

A worse option is the worn out channels of the valve body. Dirty oil will eventually foul the channels of the hydraulic plate, wedging the plungers. Or some oil seal starts to leak.

Dirty oil contaminates the channels of the hydraulic plate

The result is one - the valve body goes crazy and opens the valves to the fullest, starting to drive a huge amount of oil through itself. Oil filled with metal debris takes on properties similar to sandpaper. The aluminum channels of the hydraulic plate wear out very quickly, and very soon the hydraulic block suffers damage incompatible with further life. The abnormal pressure that he begins to apply to the box is also not good for her. A chain reaction begins, which ultimately leads to expensive repairs.

If the transition to the emergency mode of the automatic transmission is carried out only to cold or hot, the problem may be in the temperature sensor.

When you turn on the forward gear, the box goes into an accident due to the failure of the input or output shaft rotation sensors.

If the box does not come out of emergency mode at all, the electronic control unit is most likely covered.

The most disgusting thing about such breakdowns is the enormous complexity of diagnosis. The car's self-diagnosis system may not show the cause at all. And local experts will shrug their shoulders, offering to change one or the other. And the reason for everything will be a small torn wire in the very depth of the valve body.

If the box does not come out of emergency mode, then the electronic control unit is covered

What to do if the box goes into emergency mode?

The first thing to do is "reset" the error. To do this, stop the car, turn it off, wait a few seconds and start again. Next, you need to drive a few kilometers in a quiet mode and see if the error repeats itself.

The second thing to do is look at the oil level and condition. The level measurement procedure may differ depending on the vehicle model.

And finally, the third - if the automatic transmission emergency mode has not stopped - you must immediately go to the diagnostics in a normal service.

Audi A6 and C7

On Audi A6 and C7 cars, the most common reason for the automatic transmission to go into emergency mode is the failure of the solenoids and poor contacts. This is due to the new design of the Audi A6 and C7 automatic transmission, in which the electronic control unit is combined with a hydraulic plate. The electronic control unit of the Audi A6 and C7 constantly overheats, which does not have a particularly good effect on its work and resource. The solenoids in the Audi A6 and C7 automatic transmissions last about 6-8 years and then they must be changed.

The electronic control unit of the Audi A6 is constantly overheating

But if the automatic transmission of the Audi A6 and C7 has not skated so much yet, the reason is in the sensor or contacts. You cannot do without diagnostics of the Audi A6 and C7. Riding with an emergency automatic transmission on the Audi A6 and C7 is not a good idea, the boxes are not cheap.

BMW E90

The "wrong" oil can "get things done" in the BMW E90. Symptoms may include the transition of the automatic transmission BMW E90 to emergency mode, the activation of the engine cooling fan, jerking when driving, locking the selector after switching to position P, clicks when switching to N or P.

Surprisingly, counterfeit or deliberately inappropriate oil is to blame for everything. After flushing the BMW E90 automatic transmission and changing the oil to the original car, it will work as it should.

Volkswagen Vento

A Vento car can behave very strangely due to poor contact. The Vento automatic transmission will switch gears at 4000 rpm (in sport or economy mode, no difference). Vento's quarter speed will be activated at speeds over 100 km / h, and will immediately reset to low when braking. The temperature sensor can also cause the Vento automatic transmission to fail.

The temperature sensor can become the cause of the emergency mode of the Volkswagen Vento automatic transmission

ZF 4hp16

A simple and even miniature automatic transmission for small front-wheel drive vehicles. Automatic transmission ZF 4hp16 under repair is quite rare and almost eternal. If the ZF 4hp16 went into an accident - almost one hundred percent of its solenoids have survived. Sometimes the ZF 4hp16 comes across burnt clutches and a gear shift sensor. In emergency mode, it is worth looking at the ZF 4hp16 oil and remembering how long it has changed with the filter.

AL4

On cars of the Renault-Peugeot-Citroen concern with this "wonderful" box, a lot of interesting things can happen. The automatic transmission goes into error, and then the sport and snow modes light up at the same time. Snowflake and sport are bad signs for this automatic transmission and they usually signal pressure problems. And these are most likely dead solenoids or a valve body worn out by dirty oil.

Modern cars are smart and smart. Thanks to the on-board computer, cars can independently identify one or another breakdown. But what if, due to a malfunction, the emergency mode is activated?

Any modern car, regardless of class, has an on-board computer. You can't do without it today. It allows the driver to focus on driving the car, without being distracted by anything else, to closely monitor the technical condition of important components and assemblies of the car. In addition, the on-board computer has one more function - emergency mode. Let's find out what it is for and what it affects, and under what problems it turns on.

If there are malfunctions with the engine, then a special red light on the board of the on-board computer, most often it is "Check Engine" or "Engine circuit" (each brand has its own designation). In this case, the vehicle loses power. He does not completely stop, but can continue to move at low speeds, i.e. does not develop more than 2500 thousand rpm. and the speed is more than 30 km / h.

The "emergency mode" option is provided by the designers so that we can independently get to help and do not damage expensive components. This is the so-called "foolproof". By the way, the reasons for turning on the emergency mode can be, including in the engine, coolant, malfunctions in the power system.

Also, the sensors responsible for the composition of the fuel mixture may fail because of it. And sometimes, in especially severe cases associated with, the computer can turn off the motor altogether. If this is a question of a low level of technical fluids, and you have solved it, then you can try to remove the restriction yourself. This is done simply. You need to turn off the engine and start again after 5 seconds, then repeat 2-3 times. As a rule, all restrictions are then removed.

Also, emergency mode is activated due to possible. Then on the BC scoreboard the inscription "Automatic transmission" lights up in red. This can also be associated with, or with a broken contact in the box wiring harness connector. In this case, it works in an unusual way. Gear changes above 2 or 3 do not occur. You will definitely not fix this on the road. The reason may be trivial, and repairs are not expensive, but you cannot fix it without computer diagnostics.

And the last thing. If the emergency mode is activated, you cannot operate the car for a long time. The permissible maximum mileage is no more than 20 kilometers. Therefore, there is only one option - we cancel all cases and move towards the car service in order to prevent the problem from progressing.