VAZ 2114 engine cooling fan is constantly running

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Fan switch sensor, see
if the wire after the fan is shorted to ground

Is the check engine light on? If so, then most likely there is a break in the wiring to the sensor at the sensor connector. Tester in hand and forward. to check the circuits.

they have a single-contact sensor, 2 pieces, one for the brains and the fan, the second shows the temperature on the panel, they are located at the thermostat, swap them, if that doesn’t help, then look for a break in the wiring. You can’t short-circuit the sensor to ground, your brain will die.

Alena, the problem is most likely in the connector of the fan sensor, if after the connector is pulled out of the sensor and the fan still works, then it is the connector, or maybe the wires have rubbed together somewhere and the screw is bypassing the sensor.

The brains receive a signal from the sensor and control the turn-on relay. Perhaps the brain is to blame.

This is the temperature sensor that goes to the brain. either closed or the terminal is removed. The two-pin sensor is located below the camshaft sensor

For injection, control of the fan comes from the brain (supplies -12V on). On, occurs when the antifreeze temperature reaches about 100-103 degrees Celsius and opens. at 96-97 degrees. Occur on so: +12V, fan winding -12V from the brain. Disconnect from the brain should be off. fan. If off It's the fault of the brains, if not, THEN look for a short circuit to the case from the fan to the brains.

It is not the temperature sensor that needs to be replaced, but the temperature sensor, which is located on the radiator.

Tips for motorists

If the owner of the VAZ-2114 wishes, it can be equipped with an air conditioner, allowing everyone to feel comfortable in the cabin of this passenger car on these hot summer days. Then, when the air conditioner is turned on, the fan of the engine cooling system must also turn on, regardless of what temperature the coolant is. Because this is how its electrical circuit is designed when there is an air conditioner.

But, on those VAZ-2114 cars where there is no air conditioning, the engine cooling system fan should operate when the antifreeze heats up to a temperature of 101 degrees. If the fan electric motor turns on and starts working even when the engine is not warmed up, the driver will need to solve this problem.

First, you need to check the integrity of the insulation of the wires going to the coolant temperature sensor (DTOZH), which is located in the cylinder head, on its inlet pipe. If, for some reason, they begin to short to ground, then the fan must turn on, since this false signal tells the controller that the temperature of the antifreeze in the engine cooling system has risen to 130 degrees. Since the controller does not know that this signal is false, he naturally turns on the fan.

conclusions

The radiator fan on the VAZ-2114 is used to forcibly cool the engine and cooling system when natural cooling is insufficient. It turns off especially often if the temperature sensor is broken.

Its failure can lead to unexpected consequences, therefore, it is necessary to determine the cause of the malfunction in a timely manner and eliminate it . If the motorist is unable to do this, then it is worth contacting a car service center.

Good evening! I recently bought a car and started to look into it... And I came across one nuance!

When the temperature rises above 90 (98-105) the fan comes on, and it works tirelessly until you turn off the car!

On the highway at a speed of 100-120 at the previous temp. fell steadily to 90 and stayed at this level, and then there was a jamb!

I checked the pipes, they are all hot, the radiator is not cold either.

And there is one nuance, 3 days ago with a friend at 3 am we were driving along the highway and I noticed that when the speed was stable at 6-7 thousand and the heater was on, the speed dropped to 90.

Tell me where there might be a jamb, where to look (I’m afraid to go to the service station, they usually offer to change everything) maybe someone has come across this issue!

Mileage: 100,000 km

How to check the cooling system thermostat

Testing it is quite simple. To do this, you need to start the engine and warm it up to such temperatures when the valves of this mechanism operate. You can find out the temperature threshold directly on the device body. Usually it is 72 or 80 degrees. Then you need to check the temperature at the lower and upper pipes. If both are at approximately the same temperature, then the reason why the cooling fan is constantly running has been found. It is recommended to carefully inspect the thermostat valves after removing it. It is useless to repair this unit (it is easier and cheaper to buy a new one). By the way, if this element is dismantled, it can be checked without installing it in the car. To do this, the thermostat is placed in a container of water, which is then heated. Increasingly, the valve should open. If this does not happen, the device is faulty.

ECU

If the diagnosis of all other elements did not help, then the cause of the breakdown is a malfunction of the electronic control unit. But this doesn't happen often. It is not always possible to determine this malfunction on your own. Therefore, if an independent check does not give positive results, you should contact a car service center.

If the ECU fails, it is flashed to remove all existing errors or the unit is replaced. These procedures should be performed by an auto electrician. It is not advisable to do such work without experience. This device is not cheap, but, fortunately, it is replaced quite rarely. There are also several other very rare reasons why the cooling fan may not turn off. Unlike the malfunctions described above, they can usually only be identified and eliminated at a service station.

Cooling pump

Sometimes the reason why the cooling fan keeps running and won't turn off is the water pump. The temperature of the coolant in the radiator rises because its speed is slowed down. When liquid enters the cooling radiator, the antifreeze simply does not have time to cool to the required temperatures and passes to the next round. At the same time, the liquid heats up even more.

Fan device on VAZ-2114

4-blade radiator cooling fan

Before moving directly to the causes and methods of solving the problem, it is necessary to understand the design features of the unit. In other words, how does a radiator fan on a car work?

Cooling system fan design

Radiator and electric fan parts: 1 – radiator; 2 – radiator cap; 3 – electric motor; 4 – casing; 5 – impeller; 6 – rubber cushion; 7 – drain plug

It is also worth considering the electrical circuit of the radiator fan:

Cooling fan wiring diagram

The fan does not turn off: the main causes of the malfunction

Now that we know how the fan radiator works, we can move directly to the issue of identifying the reasons for its failure. So, let's look at what causes the node to not turn on:

• Wiring shorted.
• Relay.
• Temperature sensor (see “Replacing the coolant temperature sensor (DTOZH)“.
• ECU.

Elimination methods

A visual diagram of connecting an electric radiator fan with a forced activation button.

After the motorist has identified all possible causes, it is necessary to move directly to elimination methods. It is worth warning that this malfunction is associated, for the most part, with electrical circuits , where certain knowledge is required, therefore, if the motorist is not confident in his abilities, he should contact a car service center.

• Why the radiator fan on the VAZ-2114 does not turn off: signs, causes and solutions

So, let's consider the sequence of actions aimed at eliminating the problem.

Wiring short circuit

Fusion of two wires

Often, the effect of the cooling fan not turning off is the fusion of the contact group wires.

Simply put, the contacts simply close due to the fact that the wiring insulation has melted. This effect could be observed on old Zhiguli cars when they forced the fan to rotate.

The solution is to replace part of the wires, which even a novice motorist can handle. You can replace the entire wiring harness or simply replace the burnt part of the wire and insulate it with electrical tape.

Fan relay

Mounting block where fuses and relays are located. But the fan relay is located in a separate relay in the cabin. Location of the additional relay block in the vehicle interior Fan switch relay in the additional mounting block

Another problem may be the failure of the electric fan control relay, or rather its short circuit within itself . In this case, it must be removed from the mounting block and a new one installed. If the malfunction disappears, then the problem was in the relay.

Coolant temperature sensor

Original view of the coolant sensor produced by AvtoVAZ

Failure or improper operation of the coolant temperature sensor causes the fan to not turn off. If the sensor freezes, the electric fan does not work , and the ECU thinks that the engine temperature is the same as on the sensor. There will be more critical consequences if the instrument panel does not show the engine temperature.

The solution to the situation is to replace the damaged element.

ECU

Electronic engine control unit

• VAZ 2112 cooling fan does not work

Not often, but the problem becomes that there are errors in the electronic control unit, especially in terms of cooling, the electric fan does not turn off. So, the method of eliminating the problem is resetting all errors or completely flashing the ECU. It is best to entrust this process to professionals and send the car to a car service center.

Pump faults

Often, the pump does not stop working suddenly. Initially, the pump gives various signals about breakdowns - for example, the engine cooling fan is constantly running or turns on frequently.

The main reason for pump failure is the bearing - it jams or collapses. You can tell that the pump has failed by the characteristic sounds coming from under the hood. They sound like some kind of howling or knocking. These sounds can be heard even at idle. Novice motorists often do not pay attention to these noises. Pump knocks are mistaken for camshaft malfunctions. To fix the problem, you need to replace the pump. Depending on the model, it is possible to install only the front part of the pump and replace the bearing.

Relay

Often the cooling fan does not turn off due to a failed fan relay. It is installed in an additional mounting block “four”. This block is located near the front passenger's feet and is covered with a decorative trim.

It is not necessary to use a tester to detect its breakdown. It is enough to take a similar element from the owner of the same car for a couple of minutes and replace it with your own. If the fan operates normally, the relay has failed and needs to be replaced. It is inexpensive, and you can replace it yourself.

Clogged cooling system channels

Often the engine overheats due to congestion in the cooling system. The situation is further complicated by the fact that diagnosing this problem can be quite difficult. Therefore, if the cooling fan constantly works or turns on more often than usual, it would not be superfluous to flush the SOD channels. In most cases, these activities are more than enough to ensure everything works correctly. Experts also recommend not limiting yourself to just flushing, but also additionally venting the radiator.

Step by step repair

1. Initially, it is necessary to carry out appropriate diagnostics, this will allow us to determine the reason why the radiator cooling fan does not turn on in a timely manner, which will simplify subsequent repairs;
2. It is recommended to disconnect the fan connector, and then, observing the polarity, reconnect the connector directly to the battery terminal. If, with such a direct connection, the fan begins to rotate, this indicates a working drive; the reason in this case may be electrical wiring, a faulty temperature sensor, or problems with the fuse.
3. You can check the fuse responsible for the operation of the cooling fan without opening the plastic box. The fact is that such a relay is dual and is simultaneously responsible for the operation of the horn. Therefore, if the car's sound signal disappears and the fan does not work at the same time, this indicates a blown fuse. The block with such relays is located under the hood in a small plastic box. To open it, you need to remove two latches, then use tweezers to remove and change the fuse you need.
4. Relay failures are difficult to diagnose. We recommend getting a 100% working relay, temporarily installing it in the socket and checking that the fan is turned on correctly. If during such a check the fan starts working, then the relay used should be replaced with a working one.
5. To check the temperature sensor, from which the signal goes directly to the radiator, disconnect the connector from the sensor and then turn on the ignition. At the same time, the automation starts the fan for constant blowing in emergency mode. If, when the connector from the sensor is disconnected in this way, the fan turns on late, then we can therefore conclude that the temperature sensor has failed and will require replacement. The temperature sensor itself is fixed with two bolts, which can be unscrewed with a simple Phillips screwdriver. This sensor replacement usually takes no more than 5 minutes.
6. If the cause of the breakdown is still the fan, you can try to repair it first or immediately replace it with a new one. The problem may be with the bearing or brushes. In this case, you can replace such damaged parts, which will completely restore the functionality of the cooling system fan. If the cause of the fan breakdown is the electric motor, then the repair presents certain difficulties, and such a failed drive is best replaced with a new one.

In order to remove the fan with the drive you must:

1. The VAZ 2114 car is placed on a level surface and the parking brake is applied.
2. Open the hood and disconnect the negative terminal.
3. The air filter housing should be unscrewed with a ten key.
4. Loosen the clamps at the air duct.
5. We twist the screws that secure the air filter and remove the filter element.
6. Next, unscrew and dismantle the air intake, which will require an eight key.
7. Remove the fan casing by unscrewing 6 nuts with the eighth key.
8. Remove the motor block.
9. Remove the fan with the drive.

Next, you need to install the new drive or the entire fan assembly in place and carry out the assembly in reverse order. After such repairs, you should check the correct functioning of the fan, for which we warm up the engine and wait for the blower to turn on.

Air locks in the cooling system

For experienced car owners, air locks are not a secret at all. They arise due to some errors during the process of replacing the coolant. Leaks in the system are also the cause. Antifreeze cannot warm up evenly. This leads to instability in the fan operation. It often turns on or even works without interruption - hot coolant enters the radiator. Before you try to eliminate these same traffic jams, you need to check the system for leaks. If they are found, then they should be eliminated. Next you need to remove the plugs. For this you need a compressor. One tube is unscrewed from the throttle, which supplies fluid. Then a compressor is connected to the neck of the expansion tank and the air supply begins. Two to three minutes will be enough for all traffic jams to go away.

Reset errors

Sometimes after repairs have been carried out, error codes still remain in the memory of the electronic control unit. They may interfere with the normal operation of the fan and may also be displayed on the on-board computer. In order to restore the functionality of the element, you need to remove them. This can be done in two ways.

1 way. To do this, you will need an OBD scanner and a laptop or smartphone with the appropriate application. Errors are reset in the following sequence:

1. Connect the scanner to the diagnostic connector of the car and a laptop or other gadget.
2. Turn on the ignition.
3. In the program, press the READ key and press ERASE. Sometimes you need to select YES or CLEAR to clear errors in an application.

Method 2. If you don’t have a diagnostic scanner, you can use another error removal algorithm:

1. Turn on the ignition without starting the engine.
2. Open the hood and loosen the negative terminal of the battery.
3. Wait approximately 1 minute.
4. Place the terminal in place, securing it securely.
5. Close the hood and turn off the ignition.

After clearing the fault codes, you need to turn on the ignition and check for errors. You also need to make sure that the fan is functioning properly. If resetting does not solve the problem, the problem may have been identified incorrectly.

You can drive with a constantly running fan, but provided that the antifreeze temperature is normal. If it is high, then you need to stop and not use the machine until the problems with the cooling system are eliminated.

On a VAZ model 2114, the injector cooling system uses an electric fan, which is turned on by a signal from the temperature sensor.

The main malfunction is that this unit fails, which requires replacement of the fan and other components that control its operation.

Content

1How to determine a malfunction2Tools for repair3Step-by-step repair4Conclusion

Let's consider them in order.

Closure

The first and most common reason for such a malfunction is a short circuit (and most often, fusion) of the wires going to the fan. As a result of this short circuit, the electrical circuit turns on, regardless of the operation of the temperature sensor and relay. It is very simple to identify such a malfunction - just ring all the wires and check whether they are shorted (in some cases, the fact of fusion of wires can be detected even visually during inspection).

Fusion of two wires

If the “diagnosis” does not produce results, then the search for the cause should be continued, namely, checking the fan relay. The easiest way to do this is to dismantle the relay and install a new one of a similar model in its place.

Although the price of this device is low, you can do without purchasing a new relay at all. It’s enough just to borrow it for a couple of hours from a motorist friend who owns a VAZ 2114, and after checking it, return it back.

If after replacement the fan begins to operate normally, it means that the old relay was indeed damaged, and you will still have to buy and install a new one. If not, then you should move on to checking the temperature sensor.

Thermal sensor

Thermal sensor (also known as coolant temperature sensor, also known as DTOZH) is a device that reports the coolant temperature to the electronic system. As already mentioned, it is this that causes the fan to start and turn off depending on the temperature of the radiator. It is not surprising that a broken temperature sensor is a common reason why the VAZ 2114 cooling fan does not turn off.

Coolant temperature sensor

In this case, the system “thinks” that the liquid temperature is constantly high and does not drop (after all, the sensor is stuck at maximum), so no command is received to turn off the fan. To solve this problem, you will also have to purchase a new sensor and install it in place of the old one. If the fan starts working properly, then the sensor was the cause. If not, then the last possible malfunction remains - the electronic control unit.

Speaking about the temperature sensor going off scale, it is worth noting one very important point. If the cooling fan runs constantly, but the temperature on the dashboard is displayed correctly, then you can continue driving the car. If the fan does not turn off, and the instrument in the cabin shows boiling coolant, then trips should be stopped immediately and a full diagnosis of the cooling system should be carried out. This will help prevent engine overheating and failure.

Electronic module

As already mentioned, if all other elements of the electrical circuit are working properly, but the VAZ 2114 fan still does not turn off, all that remains is to check the last important link - the electronic module. It is worth noting that it rarely fails, but sometimes it does happen.

In this case, a solution to such a problem could be either a complete reset of all errors in the block or its flashing. Since it is quite difficult to do this at home, the best option would be to contact a car service.

ECU VAZ 2114

Radiator clogged

The radiator can be clogged from the outside and inside. External contamination is associated with dust and other debris, as well as insects, entering the honeycombs. This worsens heat transfer and is manifested by frequent operation of the fan and a long operating time.

Clogged engine radiator honeycomb

A good high pressure washer solves the problem. If the radiator has been in use for a long time, the car cools and heats up worse due to deformation of the honeycombs. You can “cure” this problem by replacing the radiator.

Leaking cylinder head gasket

This problem is one of the rarest causes of engine overheating in VAZ 2114 cars. When it occurs, overheating is a secondary symptom that may be accompanied by a number of others:

• oil leaks from under the cylinder head;
• uneven engine operation and low compression;
• increased oil consumption, noisy engine operation and gas flow, black exhaust.

In this situation, at best, the solution would be to replace the cylinder head gasket. At worst, a major overhaul of the engine with cleaning of all internal cooling channels.

When the engine gets hot, it is dangerous not in itself, but because of its consequences. Long-term driving at elevated operating temperatures first leads to loss of properties of elastic parts: valve stem seals and piston rings. Because of this, oil consumption increases, and engine operation becomes uneven and dirty. All this leads to expensive major repairs.

The consequences of severe overheating are even more severe: the cylinder head and cylinder block are deformed and sometimes crack. An engine that has survived this can no longer be repaired.

Additional recommendations

If desired, you can install an additional button that will forcefully start and stop the fan.

In order to do this, you will need:

• purchase a button (or toggle switch) and mount it in any convenient place (you can even under the hood);
• make a branch from the wire coming from the battery positive to the fan relay, soldering another wire to it;
• connect this wire to the first contact of the button;
• connect the second contact of the button to the relay leg, from which the “positive” wire goes to the fan.

Thanks to such a simple circuit, it will be possible to control the operation of the fan manually.

Design and principle of operation of the fan

Before you move on to repairing the fan, you should understand the principle of its installation on the cooling system. To do this, it is better to use the following simple diagram, on which the following main parts are indicated by numbers:

1. — cooling radiator.
2. - cork.
3. - electric fan motor.
4. - protective casing.
5. - fan impeller.
6. — damper pillows.
7. - coolant drain plug.

In addition, a diagram of the electrical equipment of the cooling system, which looks like this, will also be very helpful in repairs:

As you can see, the start of the cooling fan is controlled by a relay, which starts after receiving a signal from the temperature sensor.

Once the liquid in the radiator reaches a certain temperature, the temperature sensor closes and thus triggers the fan to start.

Once the temperature of the liquid in the radiator drops below a certain point, the sensor will open and the fan will automatically turn off. But, as already mentioned, sometimes this does not always happen.