Fan switching temperature for VAZ 2114 injector Fan switching temperature for VAZ 2114 injector

The fan sensor on the VAZ 2114 is needed for cooling. The fan sensor for different models has different response limits. The fan switch on for the VAZ 2114 (8 valve engine) switches on at 102-105 degrees.

The fan control module has a microprocessor with software and a microchip with contacts built into one housing. A special coating is used to protect contacts and power lines from contamination and moisture. The control module receives signals, determines the best time to activate the fan and sends the corresponding electrical signal to the relay contacts (located in the heater shaft). When current flows to the relay winding, the core moves and the open contacts short-circuit, and this drives the fan motor.

Typically thermal resistors are used as coolant or engine section temperature sensors; These are semiconductor devices that change resistance depending on temperature. As a rule, temperature sensors have a threaded connection and are installed in the nozzle of the cylinder block cover. Modern cars often have several of these sensors. There are sensors with a built-in microprocessor, which is responsible for turning on a warning lamp if the temperature of the liquid reaches a critical level.

The design of the cooling system and the principle of turning on the fan

Engine temperature indicator

Before we begin to directly consider the temperature at which the cooling fan turns on, it is worth understanding the operating principle itself. So, coolant circulates through the system and removes heat from the engine to the radiator. This element, in turn, conducts natural cooling of the liquid with a counter flow of air.

If natural cooling is not enough, the fan turns on. This happens under certain conditions.

Before considering all the factors and the temperature at which the fan turns on, it is worth understanding the design of the cooling system and the circulation of coolant:

1 – element in the form of a plug for the expansion tank; 2 – expansion tank; 3 – hose for draining liquid from the pipe; 4 – hose passing between the radiator and the expansion tank; 5 – hose leading from the radiator; 6 – tank to the left of the radiator; 7 – aluminum tube; 8 – plug systems; 9 – tank to the right of the radiator; 10 – drain plug; 11 – middle of the radiator; 12 – casing for electric fan; 13 – plastic wings of the electric fan; 14 – electric motor; 15 – toothed pump pulley; 16 – pump impeller; 17 – camshaft drive belt; 18 – engine block; 19 – pump pipe; 20 – radiator hose with supply function; 21 – heater radiator hose with drain function; 22 – hose supplying coolant to the throttle pipe; 23 – exhaust pipe; 24 – hose for refilling; 25 – heater radiator hose with supply function; 26 – thermostat; 27 – coolant temperature sensor; 28 – coolant level indicator sensor.

What should the engine temperature be?

According to the international automobile convention of December 1, 1992, where 92 representatives of the auto industry gathered, it was decided to establish a single standard for engine operating temperature.

This indicator is 90 degrees Celsius with a maximum permissible deviation of no more than 3 degrees Celsius.

Cooling fan connection diagram

But, given the region of operation and the ambient temperature, this temperature tends to rise. It is for this purpose that automakers came up with a cooling system fan, which provides additional cooling of the fluid in the system. It is driven by a temperature sensor, which detects it in the engine and is located directly on the power unit.

When the fan on the VAZ-2114 turns on

According to the decision of the convention and internal regulatory documents of the AvtoVAZ plant, the limit values for the coolant temperature are 85-105 degrees.

Thus, for normal engine operation, the system temperature should not rise above 105 degrees. This indicator is the starting point for turning on the cooling system fan. This data is stored in an electronic control unit, which regulates the operation of the fan.

The fan switching circuit looks something like this: the engine temperature reaches 105 degrees Celsius, then the sensor sends a signal to the ECU, which turns on the fan and stops it when the temperature in the system reaches 93-99 degrees Celsius.

Cooling temperature sensor

In summer and winter, as practice shows, the fan turns on at different temperatures and for different periods. In summer, forced cooling will turn on more often as the radiator is cooled by the hot air flow. In winter, the fan almost does not turn on or its operation is limited to a short period, since natural cooling is quite sufficient. Therefore, the main radiator breakdowns occur in the warm season.

The only nuance when cooling will often turn on in winter is if the thermostat is faulty (see “replacing the thermostat on a VAZ-2114”).

It was determined that the normal operating temperature of the VAZ-2114 coolant is 85-105 degrees Celsius.

In this case, the temperature at which the cooling fan turns on will be 105 degrees Celsius.

Malfunction

These components do not have a specific service life. They will last a long time if you follow the recommendations for using the vehicle and its systems provided by the manufacturer, follow assembly rules and buy spare parts made from high-quality materials. Spare parts are sensitive to high temperatures; this should be taken into account if the vehicle is used in hot weather conditions. If there are connection problems, then checking the sensor is not difficult - you just need to know where this device is located. It is located on the outlet pipe.

If the question arises of how to check the operation of the ventilation and what breakdowns may occur, then it will be difficult to answer.

Defects

cracking;
oxidation of contacts;
broken cables;
damage to fasteners;
contamination of components;
short circuit;
microprocessor melting;
fusion of plastic elements.

Fault indication

continuous operation of ventilation when the engine is running;
no fan response after the temperature rises or the air conditioner is activated;
deterioration in vehicle controllability;
reduction in the efficiency of the air conditioner.

Causes of failure

influence of humidity;
using vehicles on bad roads;
voltage instability in the electrical network;
low quality components;
incorrect installation;
violation of water tightness;
frequent overheating.

If the fan turns on, then everything is fine.

VAZ 21102 BOSCH injector The coolant temperature at which the fan operates is 107C. The antifreeze is almost boiling and oozing from all the holes, the tank cap is leaking - I’m changing it for the third time. On bad gasoline, the engine detonates (when the fan is running). Is it possible to adjust the threshold for turning on the fan as on carburetor motors (

97C). Thank you in advance. PS All services say that this is not regulated. But it doesn’t happen like that, everything is regulated here, isn’t it?

Discussion closed by moderator

Re: How to lower the sensor threshold. The temperature at which the fan turns on, determined by the control unit program, is 105 degrees. And when to turn on the fan, the unit decides! This t determines the maximum efficiency of the engine.

The switch-on temperature can be reduced only by changing the ROM firmware.

The plastic on the expansion tank is bad, and the neck is deformed, the plug does not fit tightly and the pressure in the cooling system drops, but it should be 0.9 kgcm - almost an atmosphere. The pressure decreases, the boiling point decreases (law of physics). First of all, make a sufficient sealing of the system. For the neck, it is recommended to insert a metal ring from the inside, or one made from an electric lamp socket.

What do you call detonation? Good luck! Oleg.

: VAZ 21102 BOSCH injector The coolant temperature at which the fan operates is 107C. The antifreeze is almost boiling and oozing from all the holes, the tank cap is leaking - I’m changing it for the third time. On bad gasoline, the engine detonates (when the fan is running). Is it possible to adjust the threshold for turning on the fan as on carburetor motors (

97C). Thank you in advance. PS All services say that this is not regulated. But it doesn’t happen like that, everything is regulated here, isn’t it?

At what temperature does the VAZ 2114 fan turn on?

Many motorists, while using the VAZ-2114, have encountered the fact that the engine cooling fan turns on. But not everyone knows at what temperature it should operate. This indicator is inextricably linked by the design of the cooling system and the embedded ECU software.

Motor temperature indicator

Before we begin to specifically consider the temperature at which the cooling fan turns on, it is worth understanding the operating mechanism itself. So, the coolant circulates through the system and removes heat from the engine to the radiator. This element, in turn, conducts natural cooling of the water with a counter flow of air.

If there is not enough natural cooling, the fan turns on. This happens under certain criteria.

Before considering all the reasons and temperature for turning on the fan, it is worth understanding the design of the cooling system and the circulation of cooling water:

1 – element in the form of a plug for the expansion tank; 2 – expansion tank; 3 – hose for draining water from the pipe; 4 – hose passing between the radiator and the expansion tank; 5 – hose leading from the radiator; 6 – tank to the left of the radiator; 7 – duralumin tube; 8 – plug systems; 9 – tank to the right of the radiator; 10 – drain plug; 11 – middle of the radiator; 12 – casing for electronic fan; 13 – plastic wings of the electronic fan; 14 – electronic engine; 15 – toothed pump pulley; 16 – pump impeller; 17 – camshaft drive belt; 18 – block for the motor; 19 – pump pipe; 20 – radiator hose with supply function; 21 – heater radiator hose with drain function; 22 – hose supplying coolant to the throttle pipe; 23 – exhaust pipe; 24 – hose for refilling; 25 – heater radiator hose with supply function; 26 – thermostat; 27 – cooling water temperature sensor; 28 – cooling water level indicator sensor.

According to the international auto convention of December 1, 1992, where 92 representatives of the auto industry gathered, it was decided to establish a single standard for engine temperature in operating condition.

This indicator is - 90 degrees Celsius with a very acceptable deviation of less than 3 degrees Celsius.

Cooling fan switching diagram

But, taking into account the operating region and the ambient temperature, this temperature tends to rise. It is for this purpose that automakers came up with a cooling system fan, which further cools the water in the system. It is driven by a temperature sensor, which detects it in the engine and is located specifically on the power unit.

Possible causes, their search and solution

There may be several reasons why the cooling fan turns on on a cold VAZ 2114 engine. The most likely of them are:

low level of coolant in the system;
sensor failure;
fan short circuit;
thermostat failure.

You should start your search with the first reason, since it is the most probable and at the same time the most quickly resolved. When the coolant level is low, the sensor can operate almost immediately after starting the engine, thus turning on the fan. This is due to the fact that a small amount of liquid heats up very quickly, while the engine itself is still “cold”. In order to solve this problem, you just need to add coolant to the required level.

It should be remembered that a low coolant level can lead to overheating and even engine failure, so the amount of fluid should be regularly monitored and replenished if necessary.

If it turns out that there is enough antifreeze in the system, and this is not the reason, then you should check the sensor itself. It happens that it “sticks” in the closed position, as a result of which the fan circuit is always on. You can check the functionality of the device using a multimeter.

If you measure the resistance at the sensor contacts with the engine off, the tester should go off scale or show 0, depending on the model of the device (that is, the resistance will tend to infinity). If the multimeter shows very specific numbers, then the sensor is permanently closed, and it should be replaced with a new, similar one.

It is very convenient to check the cooling system using a special diagnostic tester. It will show all possible faults, including a breakdown of the fan sensor (each element has its own error code).

If the sensor also turns out to be working, then you should check the fan. Sometimes (especially if the housing is poorly screwed on or the wires are poorly insulated), it shorts to ground, as a result of which the fan starts working directly from the battery, without the participation of an electronic circuit with a sensor. This cause can be eliminated by checking and tightening all fasteners, as well as insulating exposed wire sections.

It should be remembered that such a malfunction is quite serious and can cause:

Rapid fan wear.
Battery discharge (if you leave the ignition on without the engine running).
Car fires (due to strong heating of wires).

That is why special attention should be paid to searching for possible faults (exposed sections of wires).

The last reason that can lead to spontaneous turning on of the fan is a breakdown of the thermostat (or rather the control sensor installed on it). The bottom line is this: if the thermostat sensor fails, the electronic unit automatically starts a fan to cool the system, since the electronic unit cannot accurately control the temperature of the liquid. A kind of “reinsurance” is performed in case of possible overheating.

In order to identify a sensor failure, you will again need a multimeter. When checking, you should measure the resistance between the sensor contacts (with the engine off, of course). Normally, it should be no less than 100 and no more than 500 Ohms. If the values obtained during measurement are outside the limits of this norm, then the sensor should be replaced with a new one. Finishing the conversation about the possible reasons for the fan turning on spontaneously, we should say a few words about how to prevent them.

To do this you will need:

promptly monitor the coolant level in the system;
periodically check the condition of the electronic wires of the cooling system;
clean the sensor contacts from emerging oxides (it is recommended to carry out a similar procedure twice a year - in autumn and spring).

If you notice that the fan begins to turn on on its own, then the search for a breakdown cannot be put off until later, since the consequences (in some cases) can be extremely serious. Published September 29, 2019

Many motorists during the operation of the VAZ-2114 have encountered the fact that the engine cooling fan turns on. But not everyone knows at what temperature it should operate. This indicator is inextricably linked by the design of the cooling system and the embedded ECU program.

What is the coolant temperature limit on a VAZ 2114

I filled in the antifreeze coolant a week ago, the fan turns on around 95 degrees but still doesn’t help, in the cabin I turned on the heater all the way

maybe it's the radiator, although it doesn't look damaged

How likely is it to boil in such a situation?

Thanks in advance for any advice

The simplest thing is to take it to a car wash and let them wash your radiator grille. Next, touch the thermostat tubes to see if the temperature is correct. And the level also eats up antifreeze or antifreeze. First of all, the thermostat. I don't think the radiator clogged up that quickly anymore. After about 100 thousand it becomes clogged. By the way, you can avoid this by installing a fine mesh under the bumper. Helps. And the thermostats are extremely crappy. I don’t even know which one to recommend. I've already changed 3. And there was a master of sports, and “some kind of German”, and now a ceramic “Vladimir”. So far there are no complaints against him. Good luck

I don’t know, do you travel often in winter? In just one winter, it becomes clogged, mainly due to reagents. My brother's brake discs were cleaned with a metal brush on the jeep. It's not a matter of mileage at all.

The easiest way to check the thermostat is to start a cold engine and place your hand on the lower radiator hose when the temp. will be 90-95, the lower pipe should start to heat up.

That's what I wanted to say) you just wrote in detail, thank you)

They cleaned my radiator properly at the car wash, now it’s clear that it’s not clogged anywhere, but the fan still turns on all the time. If you drive 60-80 km, the arrow stands just shy of 1-2mm of the space on the indicator after which the fan turns on.

All the same, the thermostat is probably faulty or maybe it doesn’t open completely, I’m going to the service center to change it

All the same, the thermostat is probably faulty or maybe it doesn’t open completely, I’m going to the service center to change it, it will take 15 minutes to change it myself. At the service center, tell the pipes to be sealed and the clamps to be correct.

I installed the on-board computer so it shows the temperature for the entire journey from 94-98 degrees in the Lefortovo tunnel it showed 104 degrees despite the fact that I turned on the stove all the time, I was afraid of boiling

Tomorrow I'll go change the thermostat if it doesn't help, hi, flush the radiator, are there any special additives for antifreeze?

if this does not help, then replace the radiator and all pipes

What to do if the fan on the VAZ 2114 (2115,2113) does not work?

Overheating of the engine leads to serious problems: the pistons may jam, the cylinder block gasket may break, which leads to the need to overhaul the engine. To protect the power unit from overheating, it is important to maintain stable operation of the cooling fan. In this article we will discuss the operating principle of the device, its connection diagram, independent diagnostics and repair, as well as modernization of the control circuit. The instructions are fully suitable for VAZ 2115 and VAZ 2113 cars.

How to change the temperature?

Over time, more and more complaints appear about the operation of the cooling fan activation system. The most important design flaw is the lack of several fan operating modes and the abrupt start of its motor . Indeed, in the summer heat the fan has to work at full strength, and this is understandable. However, most often the fan produces excessive performance, which leads to rapid cooling and frequent starts.

This leads to a current overload on the on-board network.

In addition, the starting temperature threshold is too high, so the engine often overheats . Unfortunately, you can only change the fan startup parameters by reflashing the electronic control unit or upgrading the electric motor activation system. Reflashing the ECU is carried out by a competent specialist, and it is possible to set any desired temperature for turning the fan on and off.

Operating principle

A fan is a device that allows you to increase the efficiency of a cooling radiator. The radiator takes heat from the engine and releases it into the air. This process is accelerated by blowing through the blades of an electric fan.

The coolant flows through a closed, sealed system. Its task is to remove excess heat from overheated engine parts. Hot antifreeze flows into the radiator, is cooled here and returns back. While in the radiator, the coolant passes through a system of thin tubes. The incoming air flow while the car is moving helps to quickly remove excess heat from the engine compartment.

But when the car is stuck in traffic or idling, the air flow stops cooling it. In this case, the cooling system may not cope with its task. An electric radiator fan is designed to create air flow artificially. The temperature for turning on the fan on a VAZ 2114 is 85 degrees Celsius.

Having received a signal that the permissible temperature value has been exceeded, the sensor starts the device’s operating mechanism. An artificial air flow is created that removes heat from the radiator. The mechanism operates until the temperature level drops to an optimal state.

The thermal switch then receives a signal that the normal temperature has been reached and turns off the fan.

The device consists of four plastic blades that are mounted on the EDF shaft. A special controller regulates the automatic operating mode. The thermostat is equipped with a solid filler that is sensitive to temperature changes.

There are main and additional valves. When the temperature reaches 85 degrees Celsius, the main valve opens.

Diagnostics using ODB-2 scanner

The general technical condition of the car can always be checked using a personal diagnostic car scanner.

Of the options available on the market, we recommend paying attention to the Korean-made scanner Scan Tool Pro Black Edition. This model is perfectly compatible with most domestic and foreign cars

A special feature of the device is comprehensive car diagnostics. Unlike analogues, this auto scanner is capable of diagnosing not only the engine, but also ABS, gearbox, transmission, airbag, air conditioning system, etc. The device is also great when used as an on-board computer: in real time it displays speed, revolutions, readings from all available sensors, oil pressure, temperature and much more.

Where is the fan relay located?

It is located in an additional block.

4 – electric fan relay;

5 – electric fuel pump;

6 – ignition relay.

Relays and fuses may have a different order. Therefore, you need to focus on the color of the wires. The main relay is always located at the bottom. Find the relay that has a thin pink wire with a black stripe coming from it. It comes from the main relay through pin 85. Be careful! Do not confuse this with the red thin wire, which also has a black stripe and extends from the controller. And find a thick white wire with a black stripe (pin 87). This is where the cooling fan relay is located. There is always a fuse next to it. It is an element of the chain.

Connection diagram

Knowing the electrical diagram for turning on the radiator fan, it will be easier to find problems in its electrical circuit.

The cooling fan has 2 inputs: the first input leads to the generator through fuse F5 and the connection busbars in the mounting block (2). The harness block (3), nicknamed the chip by drivers, connects the electric fan via a relay to the injection controller connected to the ignition relay. From the wire coming from the controller, a branch leads to an auxiliary relay with a fuse.

Cooling fan diagnostics

If signals appear on the dashboard indicating that the permissible temperature level in the cooling system has been exceeded, this may indicate that the fan on the VAZ 2114 is not working. The main symptom of the malfunction is that the mechanism does not start even with a significant increase in temperature. It is urgent to turn off the engine to prevent its elements from overheating.

The engine should not be operated with a faulty electric cooling fan. This may damage the cylinder head.

If the cooling fan on a VAZ 2114 does not work, the following malfunctions may be the cause of the breakdown:

The fan switch sensor on a VAZ 2114 has failed.
Lack of contact at the sensor connector.
The wiring has broken.
Electric fan relay faulty.
The fuse has blown.
Damage to the device's electric motor drive.

Unplug the device. Connect it to the battery terminal. Maintaining polarity. If a direct connection to an energy source starts the electric motor, then the drive is working. There may be problems with the wiring, the fuse, or the temperature sensor.

Now it’s time to diagnose the fuse. You don't even have to open the plastic box to do this. If the relay malfunctions, the horn stops working at the same time as the fan. Therefore, if you notice the loss of the sound signal, it means that the fuse has definitely blown. You can find it in the engine compartment in a small plastic box. We release the cover, pressed by two latches, take out the burnt fuse with tweezers and replace it with a new one.

But diagnosing a relay is quite difficult. Especially for those who are exclusively “you” with auto electrics. To check functionality, the easiest way is to find a working relay and temporarily install it. If, after installing a new device, the fan begins to work properly, then it is time to replace the old one.

To diagnose the temperature sensor that supplies a signal to the radiator, you need to disconnect the connector from the sensor and start the ignition. The emergency mode will start, in which the electric fan will start blowing. If the fan starts late when the connector is disconnected, the sensor is most likely faulty. Replacing it will take no more than five minutes. You just need to unscrew two bolts using a Phillips screwdriver and install a new device in its place.

Even if a malfunction has occurred in the VAZ 2114 fan itself, this does not mean that it is time to change it. Sometimes you can simply replace a damaged bearing or brushes. But if the electric motor is faulty, it is much easier to purchase a new mechanism.

DTOZH

The radiator fan of the VAZ 2114 may not turn off due to a malfunction of the coolant temperature sensor. This device transmits information about the antifreeze temperature to the ECU. If it exceeds 101 degrees, the fan turns on to cool it down. If the DTOZh breaks down, the electronics receive an incorrect signal. Therefore, the element can operate continuously. The sensor is installed in the cylinder head on the intake manifold.

It is not necessary to call the DTOZH to check. You can borrow a known-good part for a while and evaluate the operation of the system. If everything works as expected, the sensor should be replaced. Sometimes damage to an element can be noticed visually.

When checking this part, it would be useful to inspect the wires and their connections. Sometimes the cause of the malfunction lies in poor contact or broken wiring. In this case, the connections are cleaned of contaminants and the integrity of the wires is restored.

How to make a replacement

If you are convinced that the cause of the malfunction lies in the fan motor, then the easiest way to carry out repairs is to completely replace the device. In this case, there is no point in spending money on a new casing. It will be cheaper to just buy a new electric motor.

Necessary tool

No special tool is needed. The work is carried out simply using 8 and 10 socket wrenches and a Phillips screwdriver.

Step-by-step algorithm of work

You can replace the cooling fan motor without removing the radiator.

Disconnect the connector and device wiring harness from the casing.
Unscrew the mounting bolts using a 10mm wrench.
Unscrew the lower fastening nut.
Using a 10 mm socket wrench, unscrew the mounting nut from the radiator.
Using a size 8 socket wrench, unscrew the two pressure plate nuts.
Remove the plate.
Remove the electric fan along with the casing.
Let's start dismantling the electric motor. Using a 10 mm wrench, unscrew the three mounting nuts and remove the engine along with the blades.
Using a screwdriver, pry up the lock washer.
And take it off.
Remove the impeller.
Put the impeller on the new motor. Make sure that the shaft pin fits into the impeller groove.
Reassemble in reverse order.

Replacement with draining antifreeze

If you discover that the device is not functioning correctly or is completely inoperable, you need to replace it with a new one. To perform dismantling, you must follow the instructions:

If the engine is hot, it must be allowed to cool;
De-energize the vehicle ground by disconnecting the negative terminal of the battery;
Remove the expansion tank cap;
Remove the radiator cap;
To prevent contamination, it is necessary to place a container under the drain hole;
Drain the antifreeze from the radiator. There is no need to drain antifreeze from the cylinder block. To unscrew the drain plug, just a hand is enough, so no tools are needed;
When the liquid stops flowing out, you should return the plug to its place to avoid its loss;
Remove the terminal with wires;
Use a wrench to carefully unscrew the sensor.

To install a new sensor you must:

Check the condition of the copper sealing washer. In most cases, it will require replacement with a new one. Using an old gasket is fraught with antifreeze leaks;
Screw in the new sensor, making sure that the sealing washer fits evenly;
Connect the terminals with wires;
Pour antifreeze into the expansion tank. If the drained antifreeze is of good quality, you can return it. Otherwise, fresh fluid must be used;
To eliminate air pockets in the cooling system, it is necessary to purge it;
Replace the radiator cap;
Close the expansion tank;
Connect the negative terminal of the battery;
Warm up the engine until the sensor responds.

If after these steps the fan does not turn on when the required temperature is reached, it is necessary to continue troubleshooting in other possible places. Before continuing to search for a breakdown, it is advisable to read the error log from the ECU using a diagnostic scanner.

What to do if the electric fan runs constantly?

Sometimes another problem arises. Many car enthusiasts are interested in why the fan on the VAZ 2114 is constantly running?

There are four possible causes of the malfunction:

a short circuit has occurred in the electrical circuit;
the electric fan relay has broken down;
The temperature sensor needs to be replaced;
The electronic unit is broken.

Most often, the fan starts to work continuously as a result of a shorted wire. The electrical circuit remains on regardless of the signals from the temperature sensor and relay.

To troubleshoot the problem, you need to ring each wire and find the fusion point. Sometimes it is noticeable even upon visual inspection.

If ringing does not help identify the malfunction, you need to check and replace the fan relay. The cost of the device is low. Therefore, for diagnostics it is easier to buy a new relay and install it in place of the old one.

If this does not help, then you need to check the operation of the temperature sensor. After all, it is he who is responsible for turning on and off the electric motor of the VAZ 2114 fan.

If all other elements of the system are working properly, you need to check the electronic module. It rarely fails. If the problem still occurs there, you will have to perform a complete error reset. Sometimes only a complete flashing helps. Not everyone can do this work on their own. Therefore, it is better to seek help from a car service center.

It would also be useful to install a button to force the fan to start and turn off on the VAZ 2114.

This solution can be very useful if the breakdown occurs somewhere on the highway far from the city. In this case, using the button on the instrument panel, you can force the fan to cool the engine.

Tips for motorists

The electric fan of the VAZ-2114 engine cooling system is activated only by a signal from the coolant temperature sensor. But the connection does not occur directly, but through a relay. Two fuses protect this electrical circuit. If the temperature gauge needle creeps into the red zone of the scale, then let off the gas, turn on the interior heater fan at full power and look for a place to stop .

The serviceability of one of the fuses, located in the mounting block and protecting the electrical circuit of the fan, can be checked by simply pressing the horn button. If the signal works, then everything is in order with the fuse, since it also protects the electrical circuit of the sound signal. If it malfunctions, we open the mounting block and look for a 20-amp fuse F5, but before replacing it, you need to find the reason for its failure, otherwise the newly installed one will burn out in the same way.

To check the second fuse, you will have to remove the console trim on the passenger side. There you will see three relays and next to each of them there is a fuse. You will need to pull out the middle one to check. And again, if it burns out, you need to look for the cause of this phenomenon. If the fuse is working, we check the middle relay, since the fan motor is turned on through it. Having pulled it out of its socket, inspect its contacts for oxidation. You can check it with an ohmmeter; if you don’t have one or don’t know how to use it, you’ll have to try to replace it with a working one.

Next, open the hood, disconnect the block with wires from the fan motor and, if there are a pair of wires, connect it directly to the battery. If the fan starts working, then the cause of the malfunction will have to be looked for in the temperature sensor, or a relay and another fuse located next to this relay. Well, if the fan does not work when connected directly, then you will have to look for the fault in it yourself.

The fan may not work due to a failure of the temperature sensor for turning on the fan. It is located on the cylinder head, above the thermostat. If there is no ohmmeter, we check by replacing it. Only the fan switch sensor should not be confused with the sensor that works with the coolant temperature gauge.

Another malfunction may be that the fan does not turn off after the coolant temperature drops below the one at which it should have turned off. In this case, the sensor and fan switch relay must be checked. By using the method of replacing suspected faulty devices, the driver will be able to find the reason why the engine cooling fan is not working.

Diagnostics and replacement of the fan sensor on a VAZ 2114

Every driver knows that engine overheating is very bad. It can't lead to anything good. To protect the engine from overheating, cars are equipped with radiator cooling fans. And sometimes he is far from alone.

Today we’ll talk about a very important cooling element - the fan sensor. It is responsible for turning on this cooling device in a timely manner, preventing unwanted overheating.

Appearance of the device and location

A little theory

Characteristic

Explanation

The sensor is located in the heater radiator. It is not difficult to determine that this is the one in front of you, since in the radiator it is the only element to which the wires are connected. And if you take a 30 key, then only the sensor has the appropriate fastener size.

Sensors may have different temperature limits. But for the VAZ 2114, switching on occurs at 102-105 degrees Celsius, and switching off occurs at 85-87 degrees. When choosing a new meter, focus on the one that has failed, or purchase one with an on and off indicator of 102 and 87 degrees, respectively

There is a special contact group inside the sensor. When the coolant in the radiator heats up, this group heats up and expands. When the expansion reaches a certain limit, the contacts close, they transmit a signal to the wiring and the fan turns on

Reasons for fan failure

There are a number of reasons why the fan sensor can eventually fail other than the sensor itself. Therefore, they should first be excluded to make sure that the sensor is to blame.

Reasons for fan failure include:

The fan has failed. It can wear out, lose integrity, and receive mechanical damage. It will be more expensive to replace it compared to the sensor, but there is no choice.
The chain has broken. When testing a sensor, the method of closing two of its contacts is usually used. But if the wiring circuit is damaged, this will not be possible, and due to inexperience, all the blame will be placed on the regulator.

Sensor check

First, we advise you to check the sensor that you think is faulty. Even if it turns out that it doesn't really work, at least you'll have peace of mind.

Plus, be sure to check the new sensor before installing it. This will make sure it works. Today there are quite a lot of fakes on the market, so there is always a chance to purchase a low-quality fan sensor.

Searched object

To check you will need a certain set of tools and materials, which includes:

Capacity;
Water;
Coolant;
Thermometer;
Multimeter.

Let's start checking.

Pour water or regular coolant into the prepared container.
Lower the sensor into it with the threaded part.
Connect the multimeter terminal to the regulator contacts. The measuring device must be in resistance measurement mode. Although if the multimeter has a dialing function, then choose it.
Place a thermometer into the liquid.
Heat the water.
When the liquid temperature reaches the regulator response temperature (92 degrees Celsius), the contacts should close and the multimeter will start beeping.
If this does not happen, the sensor really does not work and needs a replacement.

If you purchased a regulator that is not working, be sure to go to the store and ask for a replacement or refund. But only if you have a receipt. It is better to purchase spare parts in specialized, good stores. There is less risk of getting caught by a fake.

On an injection engine, which is literally filled with all kinds of sensors, sometimes you need to pay attention to the fan control. If the check shows that the device is faulty, there is nothing left to do but carry out the replacement procedure.

The work requires only a few tools and materials:

30 mm socket wrench;
Container for draining the cooling liquid;
Dry rags.

Having prepared everything you need, you can start replacing.

The first priority is to let the engine cool. Working on a cold engine is more convenient and safer. If hot coolant comes into contact with your skin, burns will occur.

Dismantling process

To replace, you do not need an inspection hole or overpass. For such work, these elements are not needed. A simple garage will do.
Disconnect the negative terminal from the battery.
Drain all coolant from the radiator. Do not drain the coolant from the cylinder block; this is not necessary.
Remove the plug from the expansion tank of the cooling system of your injection engine.
To drain antifreeze or antifreeze, unscrew the drain plug on the radiator. You will find it at the bottom of the radiator, and no tools are required for dismantling. The plug is easily unscrewed by hand.
Place a pre-prepared container under the drain hole where the coolant will drain. Wait until the fluid flow stops completely.
If you want to refill the same antifreeze, take a clean container. If the coolant is old enough and needs to be replaced, then the cleanliness of the container does not matter.
Screw the plug back in.
Disconnect the contacts from the fan sensor.
Using a 30 mm wrench, the regulator is unscrewed.
Twist carefully so as not to damage the plastic radiator container.
Screw the new regulator in place of the old one. Be sure to insert a copper spacer under the new device.

Copper gasket in place

Reinstall the fan control wiring.
Fill the expansion tank with pre-drained antifreeze or antifreeze.
Purge the system to avoid the formation of air pockets inside the system.
Replace the negative battery terminal.
Turn on the power unit and warm it up for a while to make sure the new sensor is working.
If, when heated to the desired temperature, the sensor does not work again, you should check other elements that may be causing this behavior of the cooling system.

Replacement without draining coolant

If you do not want to spend a lot of time replacing the sensor on your VAZ 2114, you can do without the procedure of draining the coolant.

Replacing the fan control switch without the coolant drain stage requires experience and certain skills. Therefore, it is not recommended for a beginner to use this repair method.

Using a 30mm wrench, start unscrewing the old sensor, but not all the way.
Prepare a new sensor.
Unscrew the old regulator completely with one hand, and quickly insert the new one with the other.
In this case, a certain part of the antifreeze will leak out, but this is not scary.
After replacement, be sure to thoroughly wipe all areas around the regulator with a dry cloth.
Make sure there are no leaks after installing a new device.

When finished, dry the vehicle thoroughly to ensure no coolant remains on the engine or its components. This is especially true for rubber and plastic elements.

Installing a new sensor without draining the coolant

In the injection engine of most car models, the sensor is located high in the cooling system, which allows it to be removed without a significant spill of antifreeze. To do this, you must follow the instructions below:

Do not unscrew the sensor completely. In this case, a slight leakage of antifreeze will begin;
Check the copper washer on the new sensor;
Unscrew the old device with one hand and quickly bring the new one in with the other;
After tightening the regulator, thoroughly wipe the area from any coolant drips;
Check the quality of installation for leaks.

With this method, the car owner can significantly save time. The disadvantage of this method is the need to make a replacement quickly, which can cause difficulties for inexperienced car enthusiasts. If the circumstances are unfortunate, a large amount of antifreeze may spill from the cooling system.

Keeping all elements of the cooling system in working order will protect the engine from overheating and unpleasant consequences. It is necessary to carry out timely monitoring of the operation of the regulator, especially when the first symptoms of overheating appear. Since the work requires the presence of heated fluid, all manipulations should be performed on a cooled engine. This will protect the car owner from thermal injuries.