At what temperature does the fan on the VAZ 2114 turn on?

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.

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

Video text

I will accept any help for the development of the channel: 4276 7700 1382 2587 (Sberbank).
KKl VAG adapter for computer diagnostics: https://got.by/2h9wtv Order and do the diagnostics yourself!

This is not a training video or instructions, it is just an answer to a question from subscribers.

I don’t know for what purpose many people want to change the fan switching temperature, because it is initially set at optimal. But since they ask how it can be changed, I decided to record this video.

I strongly do not recommend interfering with the firmware without the skills to work with it and understand its functioning. But if a person wants to engage in diagnostics, then he should have an idea of how to work with the firmware and how to change it. Therefore, do not be afraid to study firmware, but be wary of actions that you do not understand.

This is an introductory video and the author is not responsible for the actions of other people and the consequences that will occur if the material is used.

Before changing anything in the firmware, think about whether it needs to be changed and what these changes will lead to.

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.

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

Operating principle and temperature characteristics of the device

The operating principle of the engine cooling radiator fan switch-on sensor is based on the difference in the linear expansion of metals. When the coolant heats up, the bimetallic plate of the device changes its position. At a certain moment, the contact group closes. A signal is transmitted to turn on the fan. In some sensors, when the engine overheats, the circuit breaks.

Depending on the model, the sensors have different temperature response limits. So, to turn on the fan of the VAZ 2114-2115, a temperature of 102-105 ° C is required. The shutdown signal comes when the engine temperature drops to 85-87°C. When choosing a new sensor for his car, the car owner should focus on the old device. In the absence of the original, previous device, the necessary information can be obtained from special catalogs.

Most modern fan control systems do not have sensor limits. It does not operate in relay mode, but constantly transmits information about the engine temperature to the electronic control unit. The ECU itself sets the limits for turning the fan on and off. Changing the operating range will require brain reprogramming.

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.

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.

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.

Replacement

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.

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.

Cooling fan

Before we talk about troubleshooting, we should say a few words about the cooling fan itself. It serves to create a flow of air directed towards the radiator and serves to cool the latter. The fan turns on automatically when the temperature sensor located under the radiator is triggered.

When the coolant reaches a temperature of 100-105 C, the sensor closes and starts the rotation of the fan, which blows over the radiator and cools it. As you can see from this, normal fan activation is only possible when the engine is fully warmed up, and starting it when the engine is cold indicates obvious problems in the system.

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.

Circuit diagram for turning on the cooling fan But, taking into account 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.

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.

Exploitation

Some vehicles may use thermal switches instead of normally open control modules and relays. Typically, a bimetallic strip is included in the design of the thermal switch. When the coolant heats up to a certain temperature, the plate deforms and pushes the rod. The latter, moving, closes the contacts, and the fan is activated. When the temperature drops, the fan turns off. The operating temperature of the thermal switch may vary depending on the make of the vehicle.

Why the cooling fan does not work on VAZ-2113, 2114, 2115

The fan is designed to create an artificial air flow directed at the engine radiator in order to cool the liquid circulating in it.
When the car is moving at high speed, there is, of course, no particular need for it, but at low speeds, and also when the car is idle with the engine running, you cannot do without it. The radiator fan is turned on by a signal from the electronic control unit based on data received from the temperature sensor, which is triggered when the coolant heats up to 103-1050C. In a VAZ 2114 car, the fan is located in the engine compartment on the back side of the radiator.

Causes of malfunctions

The fan may not turn on for the following reasons:

the fan drive (electric motor) is faulty;
fuse is blown;
the relay has failed;
broken electrical wiring;
lack of contact in the temperature sensor connector;
The temperature sensor is faulty.

Search for reasons

Diagnosis of a fan malfunction should begin with the fan itself. To do this, disconnect the connector on the fan and connect it, observing the polarity, directly to the battery terminals. If it turns on, it means the drive is working, the reason needs to be looked for further. If the fan does not work, this is the reason. But let's take things in order.

The fan did not turn on. We check the integrity of the wiring and the condition of the contacts on the sensor. If everything is in order, we move on to the fuse and fan relay. They are located under the hood on the left side closer to the driver, in the mounting block.

Fuse F4 is 20A, double, for the sound signal and the cooling fan (it is very easy to check; if there is no sound signal and the fan does not work, then most likely it is the culprit).

You can check the fuse with an ordinary autotester. With relays the situation is more complicated. To make sure that this is not the case, it is better to get a one hundred percent working relay somewhere and temporarily install it in the socket for testing. If the fan does not work even with it, we go to the sensor.

If the sensor is de-energized, the controller must start the fan in emergency mode for constant blowing. Disconnect the connector from it and turn on the ignition. Turning on the fan will indicate that the sensor has failed and requires replacement.

When is it necessary to change a fan?

If the cause is still in the fan itself, you can try to repair it. The problem is usually the brushes or bearings. But it also happens that the electric motor fails due to a short circuit or break in the windings. In such cases, it is better not to experiment and replace the entire drive.

It is strictly forbidden to operate a vehicle with a non-working cooling fan. Overheating of the coolant will inevitably lead to the destruction of rubber pipes and hoses, as well as cylinder head gaskets and valve covers. In addition, high engine temperature can cause destruction of the piston group elements.

How much does a cooling fan cost on a VAZ 2114

You can buy a new cooling fan for a VAZ 2114 for 1500-2500 rubles. Replacing this part at a service station will cost 300-400 rubles. But you don’t have to spend money on this. Dismantling the old fan and installing a new one at home will take no more than 30 minutes.

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.

Replacement

socket wrench 10;
socket wrench 8;
screwdriver with a Phillips bit.

We park the car on a flat surface and immobilize it with the parking brake.
Open the hood and disconnect the negative terminal.
Using a 10mm wrench, unscrew the fastenings of the air filter housing.
Using a screwdriver, loosen the air duct clamp on the air flow sensor and remove the corrugation.
We unscrew the screws securing the cover of the air filter housing and remove the filter element.
Using a size 8 wrench, unscrew the air intake mount and remove it.
Using a 10mm wrench, then an 8mm wrench, unscrew the nuts securing the fan casing around the perimeter (6 pieces in total).
Disconnect the wire block on the fan connector.
Carefully remove the fan casing along with the drive.
Using a 10mm wrench, unscrew the 3 bolts holding the electric motor to the casing.
We put a new one in its place.
We install the structure in place, fix it, and connect the connector.
We carry out further installation in the reverse order.

Why do you need to adjust the fan temperature?

In addition to the not-so-thought-out fan response system to temperature changes, we also get a noisy electric motor that will drown out the music, and in addition the incorrect behavior of the coolant temperature control sensor. We looked into how the temperature sensor works and how it drives the electric fan on 16-valve Priora and VAZ 2110 engines not long ago.

Standard temperature sensor VAZ 2110

Moreover, the firmware of the electronic engine control unit also does not always work correctly, so diagnosticians persistently invite those who are dissatisfied with the operation of the fan to re-flash it. And yet the biggest problem with turning on the fan is that it does not have several operating modes, but throws everything out at once. Naturally, this leads to a sharp drop in voltage in the on-board network, and if it is heavily loaded with additional equipment, then this does not lead to anything good. That is, the fan on VAZ 21126 engines has a number of problems:

there are no additional operating modes, the motor always works at full strength;

excessive fan performance is good in traffic jams and in hellish heat, but not in normal engine operating modes;

the electric motor makes a lot of noise and nothing can be done about it;

the on-board network can be heavily overloaded with current at the moment the electric motor starts;

in many cases, the starting temperature of the fan does not correspond to the operating conditions and many would like to shift the lower temperature threshold another 5-7 degrees lower to avoid engine overheating.

Based on this, many people think about how to adjust the temperature at which the fan turns on.

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.