Why does the VAZ 2115 cooling fan constantly work?

VAZ 2115. The radiator cooling fan runs constantly, even when the car is cold.

We changed the temperature sensor, it didn't help. Changed the relay, didn't help. what could it be?

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

see fan switch sensor

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

short circuit of the wire after the fan to ground

maybe a kick sensor

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.

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

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.

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.

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.

you can see everything. it's most likely the brain

people, give me a hint Mark2 gx90 samurai is constantly thrashing the cooling fan, is this how it should be or is it some kind of malfunction

Source

Why does the cooling fan turn on when the engine is cold?

The operation of a car's power unit is impossible without a cooling system. If problems arise with it, the motor may overheat, which will lead to its breakdown and costly repairs. One of the main elements in this system is the cooling fan. If any signs indicating a malfunction of this device occur, the cause should be found and eliminated. Since there can be many of them, it is worthwhile to dwell on each of them in more detail.

Lack of fluid in the system

The search for a problem should start directly with the coolant, or, more precisely, by checking its level. If it is below normal, the coolant sensor will operate even on a cold engine, thereby turning on the fan. This is explained by the fact that a small amount of liquid heats up much faster. To fix the problem, you need to check the antifreeze level in the expansion tank and radiator, and, if necessary, bring it up to normal.

The coolant level must be regularly monitored and replenished as necessary, since antifreeze can evaporate, which is especially typical in the summer.

Sensor short circuit

If checking the coolant does not produce results, attention should be paid to the sensor itself. There are times when this element “sticks”, which leads to constant rotation of the electric fan. For diagnostics, you will need a multimeter, which measures the resistance at the sensor terminals with the engine running. If the sensor is working, then the device should show infinite resistance. When the multimeter displays some resistance, it means that the contacts of the sensor are closed and it needs to be replaced with a working one.

Video: checking the fan switch sensor

Short to ground

Spontaneous turning on of the fan may be caused by problems with the fan itself. The problem is that its contacts are shorted to ground. As a result, the device operates directly from the battery, bypassing the circuit with the sensor. To eliminate the malfunction, you need to check the reliability of the fan connections, insulate the wires if necessary, and tighten the fastening. A constantly running fan can lead to the following consequences:

short fan life;
battery discharge (with the ignition on and the engine off);
spontaneous combustion of wiring if it overheats.

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:

— cooling radiator.
- cork.
- electric fan motor.
- protective casing.
- fan impeller.
— damper pillows.
- 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.

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.

When the pump works somehow, the fan may indicate a problem. If the pump completely breaks down, then the engine will immediately boil - this is where serious problems and expensive repairs usually begin.

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).

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.

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.

Thermostat

Engine overheating often occurs due to jamming of this element. The fan reacts to this, in the case of the thermostat being stuck half open. At the same time, the movement of liquid through the system slows down, which causes a decrease in the efficiency of heat removal. As a result, the engine begins to overheat, and the coolant temperature rises accordingly. The fan switch sensor reacts to this. As a result, it works constantly.

Checking the thermostat is quite simple. To do this, start the engine and warm it up to the temperature at which the thermostat valve operates. This indicator is indicated on the body of the thermostat itself. We wait a little more and check the temperature of the upper and lower pipes. If both pipes are evenly hot, then the reason for the constantly running fan has been found. To be more sure, carefully inspect the thermostat valve after removing the part from the engine. Fix the problem by replacing the thermostat with a working spare part.

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

— cooling radiator.
- cork.
- electric fan motor.
- protective casing.
- fan impeller.
— damper pillows.
- 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.

The fan does not work - we change it ourselves

Try to do this: you need to remove the negative terminal from the battery (the key is “10”), and then disconnect the motor connector.

Fan power connector

If you now connect the battery again, you can call “+12” on one of the two terminals. Now you can go all-in: the negative cord from the fan is connected to ground using a T-connector. Often on the VAZ-2114 hatchback the fan does not work because it is not the wiring that is faulty, but the motor. And then they perform the replacement.

Dismantling, all steps

Once again, make sure that you have disconnected the battery. Disconnect the connector as discussed above. Next, use a socket wrench to unscrew the two nuts holding the “stopper” (see photo).

Retaining bracket above the casing

There are four nuts at the corners of the plastic frame. They need to be unscrewed with a 10mm key.

One of four nuts

The mounting frame together with the fan is removed in the “up” direction. As you can see, everything is simple.

Installation of the unit is carried out in the reverse order. It will be possible to replace both the motor and the casing frame.

Articles

2108-1309010 – casing;
2109-1308008 (-01, -02) – motor assembled with impeller;
2103-1308010-10 – impeller;
12605571 – lock washer;
16102311 – M8 nut.

Frequent causes of fan failure on VAZ 21099

In order to carry out manual diagnostics and identify a fan failure on a VAZ 21099, you need to know the basic list of the most common causes of this malfunction.

Failure of the electric fan drive.
Fuse failure.
Relay failure.
Possible electrical wiring breaks.
Problems with the temperature sensor (no contact).

To conduct manual diagnostics to identify this problem, you need to start by searching for the causes, which anyone can do.

Additional recommendations

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

VAZ 2114 fan diagram with a button

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.

Forced fan activation

If the VAZ 2107 fan sensor is broken, it is quite possible to drive on a good road without noticing it. But as soon as you drive onto a country road or get into city traffic jams, the engine will start to overheat. Replacing the fan sensor is not very difficult, but requires draining the coolant. Even if you have a spare sensor at hand, replacing it on the road is problematic. There is an easier way out of the situation.

The following operations must be performed:

disconnect “mass”;
remove two wires from the sensor terminals and connect (“short-circuit”) them;
insulate the exposed contacts of the connected wires;
connect ground.

In this case, the fan will run continuously. To turn it off, you will have to disconnect the ground and disconnect the contacts.

If you have already experienced problems with the fan sensor on the road, you can install a forced fan circuit on the car that operates in parallel with the sensor. To do this, just connect a couple of wires to the terminals going to the sensor contacts and stretch them into the engine compartment. Install a separate button (toggle switch) on the dashboard and connect the wires to it so that you can close them if necessary.

In this case, if the sensor malfunctions, there will be no need to crawl under the hood to force the fan to start.

Cooling fan diagnostics - trying to find the problem

There will be two temperature sensors: one, which is on the thermostat, is connected to the ECU. It is necessary to turn it off - leave the second one as it is.

DTOZH on engine 11183

We disconnect the connector, but do not remove the sensor itself. Then we turn the key to position 1, and so on.

Electrically, things look complicated: the fan relay is in one box, and the fuse is in another. We need fuse F5 (20A). By the way, both a fan and a horn are connected to it.

Mounting block 2114-3722010-60 and 2114-3722010-10

The main mounting block is installed under the hood, and the additional one is located at the left foot of the front passenger.

Additional mounting block (option 1)

In the additional block we see three relays. The "main relay" is located at the bottom. And then there are possible options:

The fan relay is mounted in the middle;
This relay can also be installed at the top.

The second option is shown below.

Additional mounting block (option 2)

By the way, there is always a fuse located near the relay we need. It is part of the fan circuit.

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.

Useful : Where is the cooling fan fuse for the VAZ 2114?

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.

Step-by-step algorithm of work

In each specific case, fan repair will differ depending on the existing breakdown. It is necessary to carry out appropriate diagnostics, which will allow us to determine why the radiator cooling fan on the VAZ 2114 does not turn on in a timely manner, which will simplify subsequent repairs. First of all, 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, and the reason in this case may be electrical wiring, a faulty temperature sensor, or problems with the fuse.

Wiring short circuit

One of the common reasons why the cooling fan on a VAZ 2114 constantly works is a short circuit in the wiring. To identify this malfunction, you will need to use a multimeter to test all the wires that lead to this part. Often damaged wiring can be seen by eye. Upon inspection, melted or fused parts may be visible.

Useful : 7 reasons why the fan on a VAZ 2114 does not turn on

Electric circuit

So, you have made sure that the propeller itself is spinning, that is, the directly connected motor is working. In this case, it is necessary to do the wiring, inspect all connecting blocks and terminals for poor contact.

The first thing you should pay attention to is the fuse. A 20 ampere protective device is installed on the VAZ injector discussed in this article. It is not difficult to find it - look in the block located under the hood - the one designated as F4 is responsible for the fan. In fact, the device rarely burns out, since it does not experience constant high loads. It is very simple to make sure that the element is in good working order - turn on the ignition and press the horn. The signal is also fed through F4, and therefore, if it burns out, you will not receive sound.

Broken fan

When the cooling system element in question shows no signs of life, many simply buy a new one, but this is not at all necessary. Most often, failure occurs due to abrasion of the electric motor brushes or bearing wear. Both are sold separately and can be easily changed.

It will not be possible to save the old fan of your VAZ when it has a short circuit or the winding wire has broken. Eliminating these breakdowns is impractical.

The cost of a new cooling unit is relatively high. The cheapest one sells for 1,500, and the most expensive option costs 2,500.