Why the cooling fan does not work. Why does not turn on the radiator cooling fan? Winter warming

I will tell you a way to troubleshoot the radiator cooling fan. Often happens especially in cars with big mileageIt stops turning on the cooling fan, in principle to find a malfunction, why the radiator cooling fan does not turn on, but you need to know what sequence to search. I will look for a fault without turning on the fan on the VAZ 2109, but this principle of trouble finding a fault can be applied to any machine.

Fan does not turn on the machine boys

When the car boiled down, but the fan did not turn on it, the first idea is that the problem is in the fan, or wiring. It is often a problem not in the fan A in the thermostat, it is jammed, so it ceases to circulate liquid through the radiator, therefore it does not work the radiator sensor to turn on the fan.

You can check the thermostat it is possible if the machine is boiling and the bottom of the radiator is cold, it is one hundred percent jammed the thermostat, the fan is not more. If the bottom of the radiator is hot, the thermostat works, the reason in the fan, read below.

Fan repair

Turn on the ignition in the machine.

First, check the fuse, it is shown in the photo, if you protect the whole, looking for further.

Now you can check the fan itself, the wires with a plug will be deposited from it, disconnect this plug and directly from the battery. Carefully connect the wires on the plug (plus a minus no difference) if the fan does not twist, change the fan itself.

Further, start with the simplest, it's from the radiator sensor, which will turn on the cooling fan. Remove the plug from the radiator sensor and connect each other as shown in the photo if the fan started, then the radiator sensor has deteriorated, change it.

Photo. Arrow 1 shows the fan of the cooling fan, arrow 2 shows the fan relay.

If not started, connect the wire that goes to the fuse block, right to the ground (usually it is white with a black stripe), if it started, then there is a break of the second black wire, find the break, or connect it well with the mass. Then connect these two wires together, and if the fan works, it means that the black wire with a mass is well connected. All, fixed the cooling fan, but if it did not help, then read below.

Photo. The arrow shows how to connect the wires of the radiator sensor.

Now it does not prevent the fan relay, simply replace the neighboring relays, they are the same, and connect the wires between the radiator sensor as described above. If the fan goes, then change this relay to the new one. If it does not help, read below.

Photo. The arrow shows the fan sensor on the radiator.

Now it does not interfere with checking the fan in the fuse block, take a piece of the wire and insert it into the relay connectors, as shown in the photo, if the fan is spinning, it means in the fuses block nutria, the fan voltage passes.

Photo. Checking the fuse block.

Now it does not interfere with checking the fan in the fuse block, take a piece of the wire and insert it into the relay connectors, as shown in the photo, if the fan is spinning, it means in the fuses block nutria, the fan voltage passes. If not earned, it means that in the Nutria of the block there is a break of the track, but since he twisted it, he did not disassemble him.

Photo. Verification of voltage in the fuse box, the fan relay power supply.

Check if there is a voltage on the fan relay itself, it can be done with a light bulb, as shown in the photo, it is possible and without a light bulb, just sharply read by the second end of the wire by weight, and if I'm sorry, everything works. If there is no voltage in this connector, it means there is a break of the track in the fuse box.

Photo. The arrow shows the ignition switch.

After these procedures, they found out that everything works, except for one, there is no connection with the radiator sensor, and there may be a break of the wire itself, or the outlet path to the radiator sensor wire.

Photo. The arrow is shown, the wire that goes to the radiator sensor.

It means that it remains to check the radiator sensor itself, for this, remove the switch, it is shown in the photo, since it prevents it from bringing to the plugs of the fuse block.

Remove the piers of the plugs, from the fuse block, and check the wire of the radiator sensor to the cliff, it is shown in the photo. The wire can be checked like this, connect the wire to the battery plus, and insert the other end into the chip connector, remove the plug from the sensor and connect the light bulb, or a sharp movement in the mass, if there is no voltage means there is a break of this wire.

Photo. Open wire radiator sensor.

I was lucky I found a break, but he could be in a casing, and not to get to him, then it's easier to stretch a new wire, but since at the ends of this plug wire, you can trim the plug so that the pieces of wires remain, to clean and connect with the new wire.

I cleaned the ends of the wires, twisted them, isolated, and the cooling fan earned.

The radiator cooling fan may also not be turned on if the gasket is burned under the head, the coolant does not pass into the cylinder, but the gases from the cylinder break into the cooling fluid. Thus, an air plug is created, which interferes with pumping toxol pump in the cooling radiator. A sign of a slot, take a plug from the radiator sensor, and connect them between themselves if the fan turns on, then this is not necessarily spoiled by the radiator sensor when the bubbles constantly go in the expansion tank. So the start of the gasket under the head, or the microcracy in the cylinder.

Changed toosol, or replaced the radiator, and the fan does not turn on

I observed somehow such a picture. A woman arrived at the injector VAZ 2114 for the general, replace the old Tosol to the new one. The master is straight at the Tosol's Tosol, and flooded a new one. I brought the car, check how after five minutes the engine began to boil and the fan did not turn on. Master shuffling engine, opens a traffic jam expansion tank And barely managed to run away from the departing boiling Tosol. A woman still buys five Litres of Tosola, this idiot falsoes, and everything is repeated.

It was a pity to me a woman, as it is so possible to lock the engine overheating. It came up and say, this mountain master, unscrew the water tube from the air collector and pour Tosol, until Tosol goes from this tube. And now there is an air traffic jam in the engine, it does not give normal toosol circulation, then the engine boils. He did, as I told him, I immediately earned everything, and the fan began to turn on.

If there is a toosol in an empty engine, then you must descend the air through the tube, which on the injector is connected to the air collector, and in the carburetor engines, drop the air from the collector, or from the tube that is screwed to the carburetor itself (it all depends on the machine model).

If the air does not descend, then it is necessary to wait about half an hour while Tosol does not squeeze the air stopper, gradually pouring it.

Now you can fix the cooling fan fault.

The photo shows the fan power sensor in the injector, check the performance of the sensor so that turn on the ignition, remove the plug from the sensor the fan must be screwed down with the fan everything is fine, but if it does not turn on when the engine is boiling, change the sensor new. I will not be able to twist about the injector, since it has not yet been very deliberate in the subtleties of this electronics.

Photo. The arrow shows the cooling fan switching sensor in the injection engine.

Why does not turn on the cooling fan in winter?

If the engine does not boil, there is no indication of the engine overheating sensor, everything is fine, in winter, even without turning on the cooling fan, the stove radiator is well cooled by the engine, also the main radiator is very cold, passing through it the coolant is perfectly cooled. But if you want to check the performance of the fan, then everything is written above in the article.

Repair of the radiator fan. Video.

Gorobinsky S.V.

The combustion of fuel in the CBOs cylinders is accompanied by the release of a significant amount of heat, only part of which is used by the engine and is converted into mechanical energy. The rest is useless, and it has to use special devices for neutralization of its excess. These include the cooling system, the possibility of working in any conditions provides a cooling radiator fan.

The principle of operation of the radiator fan

Before considering this issue, we will raise as a whole, which is a water system cooling in DVSshown below in the figure. It will allow us to remember the principle of its work.

In cases where a cold liquid passes through the motor shirt, it takes over heat, while the engine is cooled, and the water heats up. Then she passes through the radiator, where it gives the resulting heat into the atmosphere, and again goes into the engine.

The radiator design is a set of thin tubes that create a large cooling surface. The incoming air flow passing through it, carries out the excess heat that are stored in the liquid. In cases where there is no incoming air flow (motor operation on idling, traffic jams and other similar situations), or it is not enough to cool the water to the desired temperature, and the operation of the cooling radiator fan is provided.

For this, there is a special control scheme, the basis of which is the thermal switch of the radiator fan. It controls the temperature of the fluid. When it exceeds the set limits, the sensor is triggered, the radiator fan is turned on by its signal, which creates the necessary air flow. The heated water is cooled with this thread, and when its temperature takes the required value, the sensor turns again and turns off blowing.

So you can describe the basic principle that the radiator fan works - it turns on when the water temperature exceeds the specified, and turns off after it is reduced to the desired value.

What is fraught if the radiator fan does not work

DVS is a complex device, and its characteristics are optimal when it works at a certain temperature. As noted above, it depends on the proper operation of the cooling system. In the case when it is not possible to withstand the desired temperature, the consequences will be sufficiently sad - when overheated, the engine may well jam and then at least, at a minimum, overhaul He is provided.

The stability of the entire system should create a fan, allowing to reduce the temperature of the water in any conditions. But if it does not work, especially when it is hot, then you need to seek why the fan does not turn on or does not spin. Now such devices are usually electrical, and the refusal of the product itself is unlikely, and the possible reason for this often serves as a failure of its strapping (sensor, fuse, connecting wires, etc.).

So, finding out the reasons why the radiator cooling fan constantly works or why it does not turn on or not spinning, it is necessary first to check the device's strapping.

How to check the radiator fan

As we have already installed, the radiator fan should be turned on when the water temperature (toosol) exceeds the specified value. You can control it by the instrument readings on the front panel. If the fan does not turn on, then it is necessary to check the entire chain of signal passing.

1. Check the presence of the supply voltage coming on the product. To do this, you can use the tester or light bulb. The absence of voltage will indicate a possible fuse brave or poor contact in the wires.
2. The serviceability of the fan itself can be checked by applying the voltage directly from the battery. If he is spinning, then everything is in order with him, and the defect must be sought in other devices. If not, the fan does not spin, then the reason for the defect is in it. In principle, while you can not stand still and move on, but it is necessary to constantly monitor the engine temperature. When the arrow comes to the Red Sector, you need to stop, open the hood and cool the motor. Two receptions will allow you to move and in this case. Keep the speed of at least sixty km / h, then a constantly incident oncoming air flow will cool the water passing through the radiator, and you can move in normal mode while you maintain speed. Another technique, allowing to partially replace the non-working fan, will be the use of heating. Translate the stove to the maximum heating mode, in this case, part of the extra heat will go through the heater. True, in the cabin will be like in a bath, but you can get to the nearest one hundred.
3. To check the sensor, it is necessary to disconnect the wires and close them with each other. If at the same time the fan turns on and spins, it means that the sensor itself does not work, it is not repairable, only replacing. However, if you leave the wires closed, you can move on, with this version, the fan is constantly spinning, although it is possible that the temperature of the engine will be lowered, but it is better than standing still.

The radiator fan works constantly

Partially such a case is considered above, the reason is the temperature sensor failure or the closure of the wires on the fan. But if it is constantly spinning, it may be caused by a relay. This happens quite often, especially after the relay is triggered and the fan should be turned on.
The absorption of contacts of the relay means that they cannot open up, which is why there is a constant supply of voltage to contacts, as a result of which the electric motor is spinning constantly. The effects of the proportions of the relay contacts should be attributed to what the radiator fan does not turn off.

It is often the reason that the fan shutdown does not work, the thermostat can be. The fact is that the sensor is in the block of the block, it is it that determines when the fan is turned on. But the coolant can move along a large and small circle, when it moves in small, then the radiator does not fall into the radiator. Water movement mode determines the thermostat.

If it is jammed in the position of the movement of water in a small circle, it will be so and will move, overheat, which will trigger the sensor and turn on the fan, but because water does not enter the radiator, it will not cool, and the sensor will constantly signal about high temperatures. As a result, the radiator fan does not turn off. This case is determined simply - it is necessary to touch the hoses going to the radiator. When the thermostat jammed, then with an overheated engine they will be cold.

If the radiator fan does not turn off due to the encamping of the thermostat, then sometimes you can knock on the case to eliminate such a phenomenon. Often this happens enough, and the defect disappears. If everything remains unchanged, you will have to remove the thermostat, remove the entire stuffing from it and then put the device itself.
Another embodiment of the same defect will be the encoding of the thermostat in the intermediate position. It can also lead to the fact that the radiator fan does not turn off, but this situation is diagnosed much more difficult. A similar difficulties are caused by the fact that some water enters the radiator, but it passes too little, all the water does not have time to cool, which leads to the engine overheating.

All listed above is not complete description possible causeswhy the radiator fan does not turn off. They can be a lot, sometimes enough strange and unexpected, but in each of these manifestations of faults it is necessary to look for causes and conduct a thorough analysis.

It turns on the radiator fan early

Another extreme is the situation when the fan is turned on early. In this case, you need to look again the temperature sensor. Most likely, he needs to be replaced. Unless of course proper sensor. The fact is that the sensors are calculated for different temperatures, they are also called summer and winter, each of them should be included in its temperature range. The latter will be triggered later. And if you used all the time, you may seem that the inclusion of the fan occurs early, although it is carried out on time and everything works correctly.

It is necessary to realize how soon everything is happening. If the early inclusion is established according to the testimony on a combination of instruments, then this is not an indicator. However, when this inclusion causes anxiety, connect the appropriate equipment according to the diagnostic channel and see the real thresholds of the sensor.

Motor cooling machine - the task is the most important. If you allow the engine overheating, then at best you will need its overhaul. The ability to operate the car in any conditions is provided by the reliable operation of the cooling system, which is largely determined by the correct operation of all its components.

In the hottest summer days, the only salvation from the weak heat is the usual outdoor fan.

Not everyone can afford a full split system or at least a mobile air conditioner.

But unfortunately, this inexpensive and affordable windows, it breaks from time to time. Especially fly as seeds Chinese models.

And they are in our market the overwhelming majority. What if the fan stops rotating and work? What is his main sores and because of what it breaks?

Let's deal with more details.

Why fan does not work

In total, it is possible to distinguish 5 main reasons for the failure of floor fans:

• Old dried lubricant or its lack

• dried condenser

• Fireless thermal relay or fuse

• Vitkovo closure of windings or wiring

• Mechanical engine shaft offset

The main problem of cheap models for which for some reason few people pay attention is the wrong casting of the blades. Because of this, there is an imbalance, bearings are broken, the gaps increase.

You can't influence this, since you have already bought a fan with such an initial defect. Sometimes he seems to be working, the impeller rotates normally, but does not blow.

That is, there is no cooling flow of air from it. What is this happening?

Due to the irregular angle of attack blades. Its petals are deformed and chasing the air flow in a circle, and not throw out.

This effect can appear over time after the fan stood for a long time under the right rays of the sun and his impeller warming up, began to gradually change its shape.

It is only a replacement for the impeller to the new one.

Outdoor fan does not spin

The most common problem is the dried lubricant or its disadvantage. The fan begins to twist, lose the speed and as a result, increases the load on the engine. The windows no longer works in full force.

The engine wrapped with thin wire 0.2mm begins to warm and gradually burn out windings.

How is a similar defect detect? In this case, the fan stops rotating. He bursts, but the impeller does not spin.

And it still happens that it starts only at the 3rd speed, and the first two does not respond at all. He just lacks the power to turn the shaft.

In order to start it, it is necessary on the old airplanes, in the brazen to unwind the blades.

By the way, the same symptom may be in damage to the starting capacitor. How to find out without devices, what is the reason to blame in the breakdown?

To do this, at least get to the engine shaft, removing the protective casing and blades. If the shaft of the hand is rotated with great difficulty, then blame the dirt and dry lubrication.

And if he is spinning easily and he has inertia, it was most likely covered with Conder. Symptom - turned on the fan into the outlet, and it does not spin. At the same time, scroll into the brazen motor and it starts.

If you have hand to hold the fan blades with your hand, it can stop again. The condenser is checked by a multimeter if it has an appropriate scale measurement scale.

For replacement, select a new Conder in the same parameters that are indicated on the old housing.

By the way, not until the end of the dried capacitor also affects the revolutions. If you notice that you have fallen and the fan began to spin slowly, it is a bell to check it.

The problem of tight rotation is solved by new lubrication of bearings. Here are used, the so-called sliding bearings. Someone calls them bushings.

Apply balls in such designs is expensive, and they thunder over time they be healthy. For repair, it is not necessary to disassemble the entire engine entirely. It is enough to unscrew several cogs and sprinkle into the necessary places with the WD40 universal aerosol.

How to disassemble fan - instruction with photos

How to get to the bush, without removing the engine? To begin with, unscrew the central screw on the rear wall of the protective casing.

Another self-tapping screw is hiding in the adjusting lever button for turning or a fan head stop.

After that, the back cover is easily removed from its place. What is under it? Here you can see the gearbox of the rotary mechanism, which gives the rotation of the whole head.

Special traction is suitable for below.

Top of the engine starting capacitor.

By the way, keep in mind that in different models it can not be there. In this case, look for it near the speed button buttons.

To access the engine bearings, you will need to remove the gearbox. It is attached on three cogs, and on the bottom he supports the burden.

Twist the screws and disconnect the craving. After that, the gearbox is removed from the shaft and you get access to the rear sleeve.

You do not need to unwind anything else. The rest will be done by Wader.

Dress on the WD40 spray cylinder, a narrow guide tube and several times in the gap between the shaft and the bearing.

After splashing the WD40, turn the shaft into different directions and move it a little back and forth.

Excess thickened lubricant, extraneous garbage and dust will gradually go out. These dirt surplus are easily removed with cotton chopsticks.

If you have a thick lubricant by type of cyatim or lithol, it is desirable to apply it to the worm of the gearbox. After these cleaning procedures, dripping on the bearing with outside A few drops of oil for sewing machines.

Just do not need to apply it through Chur a lot. Otherwise, it is consequently spreading through all places and dust sticks to it, turning back into the dirt. As a result, you again get a wedge and a problem with the rotation of the fan.

Near the sleeves in separate models put felt washers. They are impregnated with oil and when heated, oil flows on the shaft, lubricating it.

It is going to all in the reverse order. Traction - three gearbox screws - outer cover.

By the way, if you tighten the central screws on the back cover through the chur, and this is the self-tapping screw, not a screw, it can pass through the plastic of the rotary gearbox and move into the shaft.

You will again have problems with turnover and jamming. Sometimes the reason for breakdown is banal and unpredictable.

With the rear bearing figured out, then go to the front of the fan. Here in the center there is a protective cap.

It is unscrewed, attention is clockwise, as the carving is left here.

Throw off it and remove the propeller from the shaft. You get access to the front bearing of sliding.

The principle here is the same. First, they squeeze and soften the old lubricant and the dirt of the waist, and then apply a new one.

After that, we dress the propeller back and close the lid. Having completed the repair, turn on the fan on high revs, and giving it to work so a few minutes, switch to the speed required.

Closure of windings or cliff

If the damage is more complex and simple lubricant does not help, you have to disassemble the fan in more detail.

First, we do all the fraud on the disassembly as described above. After removing the propeller, unscrew the plastic front lock nut, which is located immediately behind it, and throw off the entire protective frame.

In your hands, you can remain the engine and leg, in which the power wires pass and the button mechanism is located.

You disassemble this leg twisting 6 screws.

First check the wire solder. It is quite possible one of them, or even a few fell off or burned down.

If everything is going on, how to understand which wire where goes and what is responsible for? Start checking from two wires from the power plug.

One of them, let it be black (as in the photo below), through the light bulb goes directly to the fan motor.

The second wire enters the bottom terminal of the switched switch (button 0).

Next, by pressing the corresponding buttons - the 1st speed, 2nd, 3rd, the number of the switch contacts are closed, and thereby changes the engine speed.

Each wire from these buttons goes to its output on the winding, with a large or smaller number of turns. Feeding on them the voltage, you force the propeller to spin faster or slower.

Scheme of connecting the floor of the outdoor

The simplified windows diagram looks like this.

Typical schemes of most inexpensive 3-speed outdoor fans are approximately:

Pressing each button is accompanied by the closure of its contact group.

At the same time, the other contact Group At this moment opens.

Sometimes these contacts burn or do not reach their plates. Then you disappear any of the speeds.

This is checked all the elementary Chinese multimeter, in the circuit ring mode.

If you break the very first posting or there will be no contact on it, the fan motor simply does not start. Therefore, with a fully disabling fan, check first of all it.

If of course, before that, you were convinced that the fork itself is proper and the power cord from it. It is also caused by the tester.

One end of the probe put a plug on the pin, and the other touch the contact site on the "0" button. If you manage, there must be zero resistance.

Next, you can check the wires in the same way at all speeds. The contact probe on the plug is another probe on the outlet wire from the corresponding speed button to the engine.

If everywhere is zeros, then the switch and the wires you have workers.

Next, check the second contact on the fork and that wiring, which directly goes by the switch on the engine. Make sure you have a whole cord here.

Only after that you can proceed to check the windings of the engine itself.

How to check the fan winding

At the multimeter expose resistance in 2000 Ohm. Next, so as not to whistle anywhere else, at the condenser connection site, we clean a little isolation.

Look for a common point of the chain, as in the diagram below.

Having found it, call the winding resistance. For this, alternately concerns the second probe contacts on the switch.

Approximate fan winding resistance values \u200b\u200bmay be as follows:

Of course, different models, they may differ slightly, but most importantly, so that there is no cliff or KZ. Measurements can show both several hundred ohms and a little more than 1k.

It all depends on the power of the fan and the cross section of the wire.

The resistance between the conclusions of the windings will be smaller - 100-200 ohms.

The condenser winding and the total resistance of all windings together are checked.

Here is the most competent and complete video for checking the performance of the fan windings by a multimeter.

If the inspection of the integrity of the windings also did not reveal deviations and defects, go further. To do this, completely disassemble the fan, which is called bones.

Engine disassembly and malfunction

First, the engine needs to be released from all plastic parts. Remove the 4 screws from the front side and remove the cover.

On new models except screws, there are still latches. They need to bendled with a screwdriver.

To disconnect the leg, you need to find another screw, which usually hides under the plug.

Weaken it and pull the fastening shaft. To dismantle the wires that pass through the leg, they will need to bite or drop out of the terminals on the velocities buttons.

At the same time, write down or sketch where it is initially connected.

As a result, you should turn out to be a naked fan motor without all too much.

We disassemble it. Remove the screws that are tightened by the back cover.

At the same time, before disassembly, be sure to mark on all covers and gland to mark the way everything was assembled initially.

Otherwise, after improper docking, you will have a centering. There will be problems with the luxury of the shaft and the rotation of the blades.

Malfunction of thermal protection relay

After removing the bearing, you get to the windings themselves. Among the bundle of power wires running from the switch, look for a special thermorel.

Very often the engine ceases to work after its brave. This relay should work and blur chain, at a winding temperature of 135-145 degrees.

After cooling, the relay is again closed and the fan starts. So, sometimes it burns out completely and actually plays the role of the fuse.

If your fan often turned off and independently start again, it is this defense that is to blame. Know that it just does not work. This means that you have either twisted the shaft, or it comes to the end of the windings and they overheat.

Overheating windings can be associated with the destruction of a small impeller, which stands on the shaft inside the engine itself. She is designed to blow and reduce the temperature of the turns.

In the cheapest models, the thermal switch does not put the relay, everything is connected directly in them. Based on this, if your "thermal consistency" burned down, it can of course be stunned and launching windows. But at the same time you will stay without fire protection.

This relay is also checked by a tester.

There should be a chain between its paws.

Val shift and coupling

If all parts and relywoods inside are whole, it remains carefully through a magnifying glass to view windings, shaft and rotor. You may see the tormented or couhed copper veins.

This happens when the bearing pops out from its landing place and the rotor begins to beat on the windings.

In modern Chinese floor fans, it is quite often weakened by a screw connection between two semi-winds of the engine. Do not forget that the shaft is on both sides, dresses on self-centered medical sleeves, which are tightly adjusted in the lids.

When they are assembled and tightening, you can slightly push the hammer on the transformer gland, so that the shaft is spinning easily, with a small inertia. Someone is trying to catch the center on their own and cramming here such a quiet horror.

Ultimately, the shaft falls out of the bearing, as a result of which a wedge appears. As a result, the rotor begins to scratch the winding and its surface.

Also keep in mind that if your fan fell and after that stopped working and rotating, then the sleeves have most likely occurred. Can not break anything from such a fall.

The capacitor does not deteriorate from this, the windings of the scrambled eggs will not break. Is that some buttons can move away. But first of all check the coaxiality of bearings. And then everything will work as it should.

Unfortunately, with a mechanical defect of windings or rotor, as well as their intravatite closures, you can not cope with yourself. Remitting the engines of cheap windows is not rational, it will be much easier to buy a new model.

However, this is the last stage of verification, and there is hope that you will never get to it, finding damage somewhere else, the methods considered above.

Uninterrupted engine operation can be provided only in optimal temperature mode, which is why the cooling system manufacturers are paying special attention. Long ago accepted in car engines internal combustion Use air and liquid cooling. Aerial cooling It is quite simple, and it is a turbine with an impeller, which is driven by crankshaftThat is, it works constantly while the engine is running. Liquid cooling It is much more complicated, and it includes a lot of elements. One of them is the radiator cooling fan, with incorrect operation of which to achieve efficient cooling of the motor will not work.

Why do you need a radiator cooling fan

The cooling system with liquid implies that by special circles in the engine circulate cooling fluid. The first circle is "small" - it is necessary to quickly warm the coolant and bring it to operating temperature. The second round is "big", and it differs from "small" by including the radiator, where the overheated liquid cools.

The efficiency of the cooling of the liquid during passage through the radiator allows you to increase the counter stream of air that occurs when the car moves. It passes through the "honeycombs" of the radiator, removing heat from them, due to which the temperature of the coolant is more efficiently reduced. However, when moving at low speed or when the engine operates at idle, the air flow is insufficient for efficient cooling of the radiator. Accordingly, the coolant will be very hot during operation, which may result. To avoid this, the radiator cooling fan is activated, which directs the air flow on the radiator and cools it.

Types of radiator cooling fans drives

On most passenger cars The radiator cooling fan with an electrically driven is used. It is easy enough and consists of three key elements: 12 volts electric motor, impeller (fastened on the rotor) and wires (bodied to electrical system car).

Since the radiator cooling fan is required only at the moment when the cooling fluid overheats, it needs a control element. They are the sensor controlling the fluid temperature. When it is below the allowable value, the cooling fan is disabled. If the coolant begins to overheat, the sensor submits the command to turn on the fan to reduce its temperature to permissible values.

Note: When the car moves, the radiator cooling fan is almost always in the off state, thanks to the oncoming air, which cools the radiator. However, in traffic or on idling He is obliged to turn on, so that the motor overheating does not occur due to.

There are also fans cooling radiator on a mechanical drive, but they are distributed only on large trucks, tractors and other special techniques. The fans on the mechanical drive work constantly, if a special additional clutch clutch is provided for disconnecting them.

What if the radiator cooling fan does not work

Make sure that the radiator cooling fan has failed and does not work, quite simple. To do this, you need to run the car's motor and give it some time to work at idle. When on dashboard It will be seen that the temperature of the coolant is suitable for the critical zone, the sensor will report this to the radiator fan so that it turns on to work. At this point, the driver will hear additional noise from under the hood, and opening it, he will see that near the radiator spins the impeller of the fan.

If the coolant temperature has reached a critical value, and the radiator cooling fan does not think, you need to find out why it happens. The following main reasons can be distinguished, due to which the radiator cooling fan does not work:

If the radiator cooling fan does not turn on, detect the cause of the fault is quite simple, it is sufficient to perform the above test.

What to do if the radiator cooling fan works constantly

Another problem that can occur with the radiator cooling fan is its full time job. If the electric motor does not turn off or turns on too early when the temperature of the coolant is still far from the critical zone, it is necessary to establish the cause of this malfunction and eliminate it.

The operation of the cooling fan of the radiator without stopping may be related to the following problems:

It is worth noting that the permanent operation of the cooling fan is not so dangerous as its full failure, but not only in that situation when the problem is associated with the encins thermostat and overheating of the motor.

The radiator cooling fan does not work: how to use a car

If the radiator cooling fan has failed, it is better to immediately figure out what cause and eliminate the fault. But the problem may arise suddenly, and the driver must know the basic rules, how to move by car with a disconnected fan so that the engine overheating does not occur:

Do not forget that if the coolant overheats, it is better to stop and wait for a while so that it coils, how to continue moving by car with the engine overheating risk.

On Volkswagen Jet 12g. Periodically turn on cooling fans when the ignition is turned off. What could it be? How to fix the problem? (Sergey)

Hello, Sergey. Many motorists face the problem of spontaneous turning on the cooling system fans. We studied the problem and give below several recommendations for its elimination.

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Why is this happening?

If the malfunction manifests itself after you drowned the engine, then, most likely, it is associated with the radiator sensor or thermostat (hereinafter - etc.). If the device is a working, then the fan will be included in the case when the regulator at the boiling of the coolant heats the membrane and contacts the contacts. As a result, "+" will enter the relay, and from there - the valves. When the regulator fails, the fans will be turned on randomly, namely in an unnecessary temperature range.

Accordingly, first of all it is necessary to check the functionality of the regulator. You need to open the hood and diagnose the device to identify malfunctions in its work. You can try to blow the plug that comes to the sensor itself, in some cases it helps to solve the problem. Either produce it full replacementBy buying an appropriate DR official dealer Or in the store, the main thing is that it is original and high-quality. In dubious places, it is extremely recommended to buy details, otherwise you will come across more serious problems.

Before replacing, it will not be superfluous to call the wiring, in particular the area of \u200b\u200bthe chain on which Dr. itself works. Not a fact, but it is possible that the chains will also identify problems. In any case, the diagnosis is better to produce with a computer and a tester - so you can find out 100% why the fans turn on themselves. After all, we, giving recommendations remotely, cannot be sure of the malfunction, since in fact we did not diagnose the car.

Use the tester and connect it to the on-board computer and laptop. Run the diagnostic utility and check the memory on-board computer For errors. If you identify any codes, you will need to decrypt them, so you will be aware of an error. We are confident that such a diagnosis will help you solve the problem.

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