We measure the temperature at which the fan turns on on a VAZ-2110: injector and carburetor

Many owners of the domestic "ten" complain that their VAZ 2110 cooling fan does not work. The problem is quite common, but to fix it it is not at all necessary to resort to the help of specialists, or to pay a lot of money to car service technicians for finding and eliminating the cause of the problem.

All this can be done with your own hands. Today we will tell you exactly how this is done.

Circuit diagram for switching on the cooling fan for a VAZ 2110 carburetor engine.

The circuit diagram for switching on the cooling fan of the VAZ 2110 on carburetor and injection cars is different. On cars with a carburetor engine, a thermobimetallic sensor TM-108 is used for this, and on cars with an injection engine, control is carried out by a controller.

When the fan is controlled by a sensor, the switching temperature depends on the sensor setting temperature, which is indicated on the housing. If the fan does not turn on when the temperature rises to the sensor response temperature, you must first check the serviceability of the sensor. To check, just close the contacts on the sensor and if it turns on, you need to change the sensor. If after closing the terminals the fan does not work, then the cooling fan switching circuit and the integrity of the fuse need to be checked.

Where is the cooling fan relay for the VAZ-2110 car?

To keep the car engine within its temperature range, a cooling system is used. Its main parts are considered to be:

• channel for antifreeze in the cylinder block;
• pipe branch;
• thermostat;
• radiator;
• cooling fan switch sensor;
• temperature sensor;
• radiator cooling electric motor with impeller.

In this case, the last two points are attributed to the elements of the electrical part. Subsequently, the discovery of defects in the cooling system can overheat the engine, and, therefore, lead to very expensive repairs for the car.

For both injection and carburetor engines, TM-108 (bimetallic temperature sensor) is used. Moreover, in a carburetor engine it is located on the left side of the radiator. When the threaded part of the coolant heats up, the bimetallic plate bends, which leads to complete closure of the contacts.

Using a fuse, the battery voltage is transferred to one of the contacts of the electric motor, while the second one is connected to the housing and starts the impeller.

The location of the TM-108 bimetallic temperature sensor in the VAZ-2110 injectors is concentrated at the thermostat, while all signals are supplied to the electronic control unit. The signal from the unit is sent directly to the cooling fan relay, controlled by an electric motor.

Let's look at the main problems and breakdowns of the VAZ-2110 cooling fan relay:

1. The most common problem is the fan not turning on. Here you should definitely check for functionality: fuse, thermostat, sensor and electric motor.
2. The next problem is completely opposite, when the fan runs continuously without turning off. Here it is necessary to determine the breakdown and replace one of the following parts: sensor contacts, check engine lamp, and it is also worth checking whether the relay is clamped in the closed state.
3. Turn on the cooling relay when the antifreeze is already boiling. Most often this happens when the valve in the radiator cap is faulty.

You can very easily check the operation of the device yourself. Here you will need a multimeter and a thermometer. Disconnect the electrical connector and unscrew the sensor with a wrench. For safety reasons, wait until the engine has cooled down and only then remove the device, otherwise burns are guaranteed. Don't forget to drain the antifreeze in advance. After checking, when assembling the mechanism, it is better to immediately install a new sealing copper washer; besides, you should not tighten it too much.

Manufacturers engraved on the end indicate the temperature regime that must be observed and it ranges from 92 to 95 degrees. It can be checked quite easily; to do this, connect a multimeter to check the resistance, and lower the threaded part into a vessel with water. At this moment, it is necessary to start heating the water and record the moment of turning it on and, accordingly, turning it off when it cools. According to the standard, the switch-on temperature is 92 degrees, and the switch-off temperature is 87 degrees. If the deviations are much stronger, then the device must be replaced.

In order for the cooling process to occur more efficiently, two fans are installed on the VAZ-2110 - in front of the radiator and after it. But it is worth considering that when connecting electric motors in parallel, there is an urgent need to replace the wiring, since the current consumed in it will increase to 40 amperes. Don't forget to monitor your car's engine temperature. If it overheats, the antifreeze can boil, the cylinder head can become deformed, and the camshaft sometimes begins to malfunction.

VAZ 2110 fan does not turn on, causes of fan malfunction

The fan does not turn on.

But there are malfunctions in which the controller does not recognize the malfunction and the fan may not turn on when the temperature reaches above 105 degrees. C. In this case, to check the circuit and sensor, it is necessary to remove the connector from the temperature sensor while the engine is running. If the circuit is working properly and the sensor is malfunctioning, the fan will turn on and turn off when the connector is returned to its place.

If the circuit malfunctions, it is necessary to check the integrity of the fuse, the serviceability of the relay and wires, according to the circuit. For a quick check, you need to bridge terminals 30 and 87 of the fan relay, located in the heater shaft on the passenger side. If the fan works, without removing the relay from the block, connect the case and pin 86 of the relay with a test lamp, the relay should work and the fan should turn on. In this case, the controller or the wire connecting the relay to pin 46 of the controller is faulty.

If you do not hear the characteristic click of the relay turning on, and a positive signal is supplied from the main relay to pin 85 of the relay, and if there is a click and the fan does not turn on, change the relay. When installing a jumper between pins 30 and 87 does not turn on the fan, check the integrity of the fuse and the presence of power at the fan terminals. If there is power on one terminal and no power on the other, this indicates a possible malfunction of the fan motor.

Scheme for switching on the cooling fan of an injection engine.

• Scheme for switching on the cooling fan VAZ 2107 carburetor

06/09/2011 “If you notice an error in the text, please highlight this place with the mouse and press CTRL+ENTER” “If the article was useful to you, share the link to it on social networks”

To ensure safe and stable thermal conditions of an internal combustion engine, precise operation of the cooling system is required. The slightest failure will lead to overheating of the engine, which can lead to burnout of the head gasket or failure of the piston group elements.

The radiator fan is one of the key components of the car cooling system. Its role is to promptly force cool the liquid in the radiator. Problems with turning it on are a common occurrence for our cars.

In this article we will talk about possible reasons why the VAZ-2110 cooling fan does not work, and also consider options for eliminating them. But first, let's understand its design and operating principle.

When does the radiator fan turn on on a VAZ-2110

To really understand how to change the fan switching temperature on a VAZ-2110 injector, you need to know exactly the factory design parameters and the principle of fan switching itself.

In carburetor engines, the fan turned on at about 100 degrees.

On old-style 2110 carburetor engines, the fan was turned on using a thermobimetallic sensor. It was installed directly in the radiator bank and set to a certain temperature. Since the normal operating temperature of antifreeze is 80-90 degrees , the bimetallic plate made contacts at approximately 100-105 degrees .

In a carburetor VAZ-2110, the sensor is located in the radiator.

In an injection engine, the sensor is located in the cylinder block.

In injection tens, the fan starts in a completely different way. There are two temperature sensors installed near the thermostat - one with one wire, the second with two. The first one is responsible only for the temperature indicator needle, so there is little demand from it. The second sensor with two wires is working. It is he who supplies the impulse to the electronic engine control unit, which then supplies power to the fan motor network.

Scheme.

Features of the temperature sensor

However, one must understand that a temperature sensor is a conventional converter of thermal energy into a variable electrical pulse. More precisely, when the temperature of the antifreeze changes, the resistance of the sensor changes approximately in this mode:

Now the principle of operation of the fan activation system becomes clear - the ECU receives a certain electrical impulse when the temperature reaches 110 ° C (133 Ohms) and supplies power to the fan motor.

As soon as the resistance of the sensor element rises to 187 Ohms (which corresponds to 97 °C), power is removed from the fan and the engine cools down.

Fan connection diagram in carburetor and injection engines

The control of forced radiator airflow in carburetor and injection engines of the VAZ-2110 is significantly different. Firstly, the fan switch located on the radiator housing is responsible for everything. It is set to a certain coolant temperature. Usually it is 105-107 oC. When the coolant heats up to this temperature, the sensor is triggered, sending a signal to the fan relay. It closes the electrical circuit, driving the electric motor.

• Coolant temperature sensor: where it is located, how to check and replace

Turning on the cooling fan of a VAZ-2110 with an injection engine occurs somewhat differently. In engines equipped with an electronic control unit, there is no sensor on the radiator. Its place was taken by a temperature sensor located on the thermostat pipe. When the coolant heats up to a temperature of 105-107 oC, it sends a signal directly to the controller, which makes the decision to turn on the fan. It transmits an electrical impulse to a relay, which turns on the electric drive.

Sensor for turning on the fan of a VAZ 2110 car

Internal combustion engines are far from perfect, so most of the energy consumed during the operation of such units is released in the form of heat. In the winter season, this “by-product” can be successfully used to maintain optimal air temperature in the cabin, but in the summer this is not necessary, so antifreeze can boil even after a short period of operation of the internal combustion engine. When the coolant heats up to a certain value, the fan automatically turns on and the coolant temperature returns to normal. The VAZ 2110 fan switch-on sensor, with the help of which the forced cooling of the internal combustion engine is timely activated, will be discussed in this article.

Possible faults

If the VAZ-2110 cooling fan does not work, do not rush to contact a car service center. You can determine the cause of the malfunction yourself. Moreover, it is not at all necessary to have special skills for this.

The cooling system fan may not turn on due to:

• electric drive malfunctions;
• blown fuse;
• faulty thermostat;
• a failed fan switch (temperature);
• faulty relay;
• broken electrical wiring;
• faulty expansion tank plug.

Design

Cooling system diagram
The cooling system includes many components. Among those that interest us today, which can cause problems with the radiator fan, we note:

• Electric fan. This unit starts working when the coolant temperature reaches 100-105 degrees Celsius;
• Fan switch sensor. It is configured to operate precisely within the specified temperature range. The sensor is located on the inlet pipe of the cylinder block (labeling from the sensor factory is LS0112);
• Fuse marked F7. It is located in the mounting block;
• Fan relay. You will find this unit already in the cabin, under the right panel of the front console.

If the radiator fan does not work on your VAZ 2110, the cause of the malfunction should be looked for in the above-mentioned system elements. Although there may be one situation in which the electrical circuit has nothing to do with the fault.

How to check the thermostat

The function of the thermostat in an internal combustion engine is to regulate the flow of coolant, directing it in either a small or large circle. While the engine is cold, its valve blocks the flow of coolant into the cooling radiator. This allows the engine to warm up faster.

When the coolant warms up, the thermostat valve opens, directing it to the radiator for cooling. If the valve jams, the coolant constantly moves in a small circle, not reaching either the fan switch sensor or the temperature sensor. In this case, the liquid may even boil, but the sensors, being uninvolved in such a circuit, will not work.

Check the thermostat by determining the temperature of its pipes by touch. When the engine is warm, they should all be hot. If the pipe leading from the thermostat to the cooling radiator is cold, the locking device is faulty.

• Injection on a classic: wiring diagram for a VAZ 2107 injector to help the car owner

How to check the sensor

One of the most common reasons why the VAZ-2110 cooling fan does not turn on is a non-working sensor for its activation (for carburetor engines) or a temperature sensor (for injection engines). Let's consider ways to check them for different engines.

In a car with a carburetor engine, you must turn on the ignition and short-circuit the two wires going to the sensor. The fan should turn on. If this does not happen, the problem is definitely not with the sensor.

For injection cars, it is necessary to warm up the engine to operating temperature and disconnect the sensor connector, disconnecting it from the vehicle’s on-board network. In this case, the controller must start the fan in emergency mode. The electronic unit perceives this as a failure in the cooling system and forces the fan drive to operate in constant mode. If the drive starts, the sensor is faulty.

Checking the cooling fan relay

The most difficult step in troubleshooting a fan is determining the functionality of its relay. It is only relatively possible to establish its serviceability at home. But you also need to know where the cooling fan relay is located.

And it is located in the additional mounting block of the center console. On the lower left side of the front passenger side there is a plastic cover covering the console. To open it, you need to unscrew four screws. There are three relays under the cover. The leftmost one is responsible for turning on the cooling fan. You can check it only by installing a known-good device in its place. After the engine has warmed up to the sensor response temperature, wait for a characteristic click. If the cooling fan relay does not work, you need to check the wiring.

How to check the fan circuit

1. We start the test with the simplest thing - determining the condition of the fuse.
We are looking for it in the mounting block, which is located under the hood. Its marking is F7. 2. We take it out, and visually, or using a multimeter, check for functionality. If it burns out, replace it with a new one (20 A). If everything is fine with him, we put him in his place and move on.

3. In order not to waste time, it is better to immediately determine the functionality of the fan motor. To do this, disconnect the wires from it and connect it directly to the battery, observing the polarity. If the fan is “alive”, we continue to look for the cause.

4. Move on to the fan relay. It is located in an additional mounting block in the car interior to the left of the front passenger's feet.

5. There are three relays there. Ours is on the far left.

It is unlikely that you will be able to check it yourself; it is better to take another one somewhere and put it in the place of the person being checked. We heat the motor to maximum temperature and observe the behavior of the fan. If there is no result, move on.

Unscrew and inspect the cap of the expansion tank. At the slightest suspicion of leakage, throw it away and install a new one.

Next we move on to the sensor itself. We start the engine, heat it to a temperature of more than 100 0 C, and disconnect the connectors from the sensor. The ECU that controls the operation of the sensor should automatically send a signal to the relay to force the fan to turn on. If the fan turns on, the problem is most likely in the sensor. We replace the sensor with a new one and check its operation.

If nothing works here, you need to look for an open circuit in the electrical circuit. To do this, it is better to contact specialists.

Source

How to check wiring

Finding a broken conductor in a car's electrical circuit yourself is not at all difficult. It is necessary to check (ring) all wires in the indicated areas with a tester.

For carburetor engines:

• from the switch on sensor to the fan;
• from the fan to the mounting block (fuse);
• from the mounting block to the relay.

For injection engines:

• from the main relay to the fan switch relay;
• from the switching relay to the fan and controller;
• from temperature sensor to controller;
• from the fan to the mounting block (fuse).

If a wiring break is detected, it must be restored, as well as the possible cause of the circuit break must be identified and eliminated.

Expansion tank cap

The last reason why the VAZ-2110 cooling fan does not work may be a malfunction of the expansion tank cap. The fact is that when the engine is running, a pressure above atmospheric pressure is created in the cooling system, due to which the water, which is part of the coolant, does not boil at 100 ° C. The expansion tank cap valve is designed to maintain the required pressure. If it fails, the pressure in the system will be equal to atmospheric pressure. This will cause the coolant to begin to boil already at 100 degrees. A sensor designed to turn on at a higher temperature will naturally not work.

It is unlikely that you will be able to check the operation of the cover at home, so if during a visual inspection you have doubts about its functionality, it is better to replace it immediately.

The principle of operation of the cooling system of the VAZ 2110 injector 16 valves

The design is a closed circuit, inside which coolant is pumped through a centrifugal pump. The radiator releases the temperature generated by the engine into the atmosphere. The sensor installed on the thermostat pipe senses the coolant heating threshold of 105 - 107 degrees Celsius, provides information to the controller. The controller sends a signal to the relay, starting the electric motor of the fan. The radiator honeycombs are blown.

The principle of operation of the cooling system of the VAZ 2110 injector 16 valves: 1 - heater radiator; 2 — coolant drain hose from the heater radiator; 3 — coolant supply hose to the heater radiator; 4 — coolant pump hose; 5 — expansion tank hose; 6 — steam removal hose of the heater radiator; 7 — expansion tank cap; 8 — expansion tank; 9 — thermostat; 10 — coolant drain hose from the engine radiator; 11 — hose for supplying fluid to the throttle assembly; 12 — steam exhaust hose of the engine radiator; 13 — hose for supplying fluid to the engine radiator; 14 — engine radiator; 15 — radiator drain plug; 16 — electric engine radiator fan; 17 — coolant pump; 18 — supply pipe of the coolant pump; 19 — coolant drain hose from the throttle body.

Safety regulations

• Open the expansion tank cap after the engine has cooled down.
• When working under the hood, beware of rotating blades and a hot engine.
• Use auxiliary, serviceable conductors with a cross-section of 2 mm.
• Use standard fuses of the required rating.
• Use a proper tool.
• Insulate “bare” contacts, avoiding short circuits in the electrical wiring.

Possible cooling fan malfunctions

There are seven known reasons why the fan on a VAZ 2110 does not turn on.

1. The safety valve of the tank is stuck and not sealed.
2. The integrity of the conductors is broken, there is poor contact at the connection points of the circuit elements.
3. The fuse link on the control panel has burned out, there is no contact in the fuse sockets.
4. The temperature sensor is faulty.
5. The relay for turning on the electric fan drive is damaged.
6. The fan motor has burnt out.
7. The controller is faulty.

Electrical circuit malfunctions

If everything is fine with the tank cap and there are no problems with pressure, then the causes of the radiator cooling malfunction should be sought in its electrical circuit.

1. The search begins with checking the functionality of the fuse marked F7. To do this, you have to get to the mounting block. Check the quality of the contacts and the presence of traces of oxidation. If everything is good here, we move on. If the contacts are broken, simply clean them, or simply change the fuse. This is a small financial cost.
2. The next place to check will be the VAZ 2110 fan switch sensor. You do not have to go to a specialized service station to check the efficiency of the sensor. This is done in a garage: Warm up the engine of your car to above 100 degrees Celsius;
3. Turn off the engine, then start the engine again;
4. Lift the hood and remove the terminal from the VAZ 2110 fan sensor;
5. If after removing the element the fan begins to spin, then the unit is working properly, but there are problems with the sensor;
6. When on a VAZ 2110 the cooling system fan does not turn on after disconnecting the terminal, the situation is the opposite - the fan does not work, but the sensor is in good condition.

Procedure. Step-by-step instruction

If after completing the next step the problem goes away, further checks are stopped.

1. Open the hood.
2. Wait for the engine to cool down.
3. Make sure that the expander cover elements are in good condition. Remove scale, rust, clear holes, wipe, assemble. The absence of noticeable damage to parts gives hope that the product will work.

Inspect the electrical wiring elements to ensure a reliable connection

Possible factors for damage to electrical circuits:

• vibration;
• oxidation;
• burning;
• breakage, fraying of electrical wires;
• insulation aging, short circuit.

Switch the tester to resistance measurement mode. Remove it with special tweezers and ring the fuse link F7 located in the mounting block.

Fuse box diagram

Attention! It is important to find out and eliminate the cause of burnout.

Replace the burnt-out element with a serviceable one with a rating of 20A. Inspect and clean the nest. Insert fuse.

It was not possible to find out the reason, the protection triggered again - look for a short circuit.

How does the engine cooling system work? Diagram

Disconnect the fan plug. Use a tester to measure the circuit of the electric motor windings. Zero resistance or a break indicate the need to replace the radiator blower electric drive.

Interturn short circuits that cause multiple replacements of fuse links cannot be measured with the device.

Sensor check

Start the car. Pull out the coolant temperature sensor connector. The fan starts working - the sensor needs to be replaced. Secure the disconnected wire. Drive to a nearby service station.

Relay test

There is a hatch on the floor at the front passenger's feet.

Below it is a built-in panel with three relays of the same type:

• fan installation;
• fuel pump;
• ignition (main thing).

By replacing each other, try to start the airflow. The VAZ 2110 fan does not work - go to the next step.

Where is the VAZ 2110 cooling fan relay located?

If you are wondering where the fan relay is located on a VAZ 2110, then this photo below will answer your question and you can easily find where the cooling fan relay is located on a VAZ 2110.

VAZ 2110 fan relay

Check the electric motor

• The only correct solution is to turn on the airflow directly and urgently visit a service station.
• Prevention of breakdowns of the cooling system of the VAZ 2110 injector 16 valves.
• Periodically inspect the components of the cooling system.
• Monitor the cooling temperature on the device, listen to the operation of the fan.
• Maintain coolant level. Replace after 2 years or 30,000 km.
• Use the solution to remove rust and scale.
• Signs of a change in the properties of the coolant are a change in color, an increase in fluidity.
• Check the density with a hydrometer.
• Do not mix coolants.
• Every twelve months, rinse the expansion tank cap with water and check it on a stand with a pressure gauge.
• Avoid contact of aggressive liquids with electrical wiring and electric motor windings.

Purpose of the fan switch sensor

As we have already mentioned, the DVV is part of the engine cooling system and duplicates the function of the thermostat. The main task of the sensor is to protect the vehicle’s power unit from overheating and promptly give a command to the ECU to turn on the fan. How does he work?

While the engine is running, the coolant temperature may rise. As soon as it reaches a certain level, the DVV gives a command to the electronic unit of the car.

The fan immediately starts and powerful air flows over the radiator. As a result, the coolant temperature decreases to the optimal level much faster.

Fan sensor location

Finding the sensor is not difficult - it is located directly in the radiator. A more precise location may vary (it all depends on the design features of the model of a particular year of manufacture).

For example, the DVV can be located in the right or left tank, in the lower or upper part of the radiator.

Finding the location of the sensor is not difficult. This is almost the only unit on the radiator from which wires extend. Another distinctive feature is the large nut head, which can be unscrewed with a “30” wrench.