Signs of a malfunction of the temperature sensor VAZ 2114

Types of coolant sensors

The temperature sensor is a variable resistor that changes the resistance reading depending on the engine temperature. There are two types of temperature sensors on VAZ 2114 cars:

• Coolant temperature. Used by the electronic control unit to determine the temperature in the cooling system. Based on the information received, the ECU turns the fan on/off and changes the composition of the fuel-air mixture.

• Coolant temperature indicator. Transmits indicators to the pointer device. In this way, the driver is informed about the temperature of the power unit.

Checking the sensor yourself

As you can already understand from the above, the temperature sensor transmits the level of heating of the coolant to the dashboard to the driver, so that the driver can independently visually assess its condition.

And in order to diagnose it, you need to do the following:

• We start the car in advance, let it idle until the needle shows the maximum operating temperature, that is, 90-98 degrees.
• Next, you need to disconnect the contacts and look at what the arrow on the instrument panel will indicate.

In this case, there may be two types of further course of events.

1. The arrow remained motionless and does not react in any way to what is happening - the reason lies in the wiring or in the sensor itself. It is necessary to check the wires themselves for integrity, and only then proceed directly to the sensor.
2. The arrow goes to “zero” - in this case it is necessary to check the fuse. If the fuse in the block is intact, and when the contact closes to ground, the arrow begins to jump, the temperature sensor does not work.

Checking with a multimeter

Checking the operation of the coolant temperature sensor with a multimeter

Before you start testing in multimeter mode, you need to prepare a container that will be able to withstand a temperature of 100 degrees, a water thermometer and a boiler, with which we will heat the prepared antifreeze for testing the sensor.

1. On the multimeter, set the values ​​to ohmmeter test mode.
2. Next, we attach the probes to the body and to the sensor contacts.
3. We put the sensor in a container with antifreeze and slowly begin to heat it.

We compare the data you receive with the results of a fully functional device. And if they are lower or higher than these readings, then the sensor can be considered faulty.

Thermometer and multimeter readings with resistance test mode.

This method makes it very easy to check both new and used sensors.

Where is the engine temperature sensor located on the VAZ 2114?

The location of the DTOZH depending on its type. The engine temperature sensor on the VAZ 2114 is located at the junction of the outlet pipe of the cooling jacket and the thermostat . For unobstructed access to the part, you will need to move the air filter housing to the side. You can determine the location of the sensor in more detail by paying attention to the photo.

The DUTOZH is located
below the thermostat in the cylinder head .

Both sensors are installed on the power unit using a threaded connection. The transmission of information to the electronic control unit and the pointer indicator is carried out using wires. You can determine the type of part without having specialized education. To do this, just count the number of wires connected to the part. The coolant temperature gauge sensor is connected using one wire, the DTOZH is connected using two.

Checking the DTOZH

DTOZH transmits a signal to the dashboard, which shows the driver the level of antifreeze heating.

How to check the temperature sensor on a VAZ 2114:

1. We start the car, look at the instrument panel, the arrow points to the maximum, and the engine is cold as ice, we disconnect the contacts from the temperature meter: the arrow has dropped to a minimum - it’s time to replace it.
2. If the arrow remains at the maximum, look at the DTOZH contact, it may be shorted to the car’s ground.
3. The engine warms up normally, but the needle jumps or lies at zero - check the fuses.
4. If the fuses are normal, close the contact to the ground of the car - the arrow jumps up - the temperature sensor on the VAZ 2114 does not work.

Another great method:

• Take a multimeter and set it to ohmmeter mode.
• You also need a good thermometer with a maximum of over one hundred degrees and a container that can withstand hot antifreeze.
• We attach the multimeter probes to the body and the sensor terminal.
• Place the connected DTOZH in a container with poured antifreeze or antifreeze and heat it up.
• We look at the indicators of the thermometer and ohmmeter:

Signs of DTOZH malfunction

The owner can independently determine the need to replace the part. Part failure is accompanied by the following symptoms:

• Increased fuel consumption. Based on incorrect data, the ECU incorrectly selects the ratio of fuel and air mass in the working mixture. A rich mixture with a warm engine leads to increased consumption.
• Engine overheating. Turning on the cooling fan late leads to an increase in the temperature of the liquid in the jacket. When the power unit overheats, metal parts expand, which increases friction between the rotating parts and reduces their service life.

• The engine takes a long time to warm up. The cooling fan operates in advance. The liquid passing through the radiator is constantly cooled. This leads to a decrease in temperature and an increase in the warm-up time of the power unit.

Temperature meter sensor malfunctions

Knowing the location of the device, it is easy to get rid of the breakdown yourself. The main reasons for the incorrect operation of the device, according to experts, may be:

• lack of contact;
• rupture and wear of insulation, loss of contact integrity;
• the device is completely out of order;
• The fan is not working well.

Signs that should alert the driver of a VAZ-2115 and prompt them to diagnose the condition of the antifreeze temperature sensor may be:

• fan operation when the machine engine is not warmed up;
• the engine is warmed up, but still refuses to function;
• Fuel costs are gradually and steadily increasing.

How to check DTOZH?

If signs of failure of the DTOZ appear, its performance should be checked. In some cases, incorrect operation of the cooling system may be due to damage to the wiring. You can check the DTOZH yourself at home. To do this you will need a multimeter and a water thermometer. For diagnostics, set the multimeter switch to resistance measurement mode. After this, place the working surface of the part in a container with water.

During the testing process, it is important to ensure that liquid does not get on the terminals of the product. Failure to comply with this rule will result in incorrect data. Using a multimeter, measure the resistance between the contact pads. As the temperature of the liquid in the container increases, the resistance indicators should change. The photo below shows the dependence table. Please note that indicators may vary slightly individually for each case.

If during the diagnostic process it was possible to determine that the sensor is working, it is necessary to check the integrity of the wiring. In some cases, the contacts close together. This leads to malfunctions in the cooling system. A failed sensor must be replaced. Repairing the part at home is not possible.

How to check a temperature sensor?

Many will say that this is a crazy idea, since the fairly low price provides the opportunity to purchase a new element. But this does not stop the Kulibins. Checking the sensor is necessary in order to determine the root cause leading to heating of the motor.

To check an element, you must perform the following steps:

1. 1. Draining antifreeze.
2. 2. Removing the temperature sensor.

Dismantling

By its design, the device consists of a small threaded bushing that is screwed into the manifold. A thermocouple is installed in the center of the element, which controls resistance to changes in temperature.

If the device is not working, there is no point in completely disassembling the sensor. The best solution would be to recycle it.

If you doubt that it is faulty, check it using a thermometer. The resistance of the cold sensor should be 1500 Ohms. During heating, the resistance readings change. At a heating temperature of 70 degrees it should be 300 Ohms, and when boiling - no more than 90 Ohms.

This is the only way to confirm its functionality.

When purchasing a new sensor for a VAZ 2114, you need to use a key number 21 to put it in place. For strength, add a small amount of sealant to the threads, do not forget about the coolant in the radiator and engine cylinder block, check its performance.

How to replace the temperature sensor?

You can replace the part yourself without resorting to the help of specialists. For ease of dismantling, it is better to choose a socket wrench or a deep socket with a knob.

Replacement is carried out on a cold engine in the following sequence:

1. Remove the air filter from the car. It blocks access to the sensor. After replacement, you will need to install the filter in its seat.
2. Disconnect the negative cable from the battery. Necessary to avoid errors in the electronic control unit.
3. Remove the protection located under the power unit.
4. Drain the coolant from the radiator.
5. Disconnect the wires from the sensor. When disconnecting the connector, it is important not to damage the plastic latch. It is necessary to fix the plug and prevent it from spontaneously disconnecting.

1. Unscrew and replace the sensor. A 19 mm socket wrench is used. To speed up the work process, you can use a head with a ratchet.
2. Reinstall the electrical wiring plug and protection.
3. Fill with coolant and warm up the power unit to operating temperature.

Some car owners replace the sensor without draining the coolant. To do this, carefully unscrew the part and quickly replace it with a new one. Thus, during the replacement process, a minimum amount of coolant leaks.

Checking the two-pin sensor

The responsibility assigned to the controller does not allow it to be checked as easily as the previous one. The fact is that the correct operation of the engine directly depends on it. With its help, the optimal quality of the working mixture is selected and the fan is turned on, and this happens at a certain, predetermined temperature. Changing its parameters can lead not only to additional expenses, but also cause, albeit indirectly, the failure of the power unit.

Checking the two-contact engine temperature sensor of the VAZ-2115 is more painstaking and time-consuming. It is done in the following sequence:

While the heat has decided to tinker with what I can do myself) Another problem is that the fan does not work when the engine heats up, because of this I have to drive with the heater on, and in the summer it’s hell ((The fluid had to be changed anyway, but at the same time I decided that’s all replace the leaking water so as not to do double work, since before replacing the thermostat, you need to drain it. When it was cold, I carried out all the work naturally. The first mission was to drain everything that was already flooded... I decided to drain it from the engine first. Well, as recommended, I covered the generator with a bag so as not to get wet.

I removed the air filter so as not to interfere, and the minus from the battery.

I had to tinker with the air filter, since one side unscrewed without problems, but the other did not, so I had to pull out the rubber cushion and the problem was resolved.

Typical signs of DTOZh failure

After some time, all malfunctions that occur in the circuit are entered by the controller in the form of a code into the ECU memory.

A signal about engine malfunctions is sent to the instrument panel in the form of a lit “CHECK ENGINE” indicator light.

Signs of a faulty meter on a VAZ 2114:

• turning on the fan when the engine is cold;
• fuel consumption increases;
• There are problems starting a warm engine.

Main faults:

• lack of contact with the device;
• rupture of contacts, violation of insulation;
• sensor failure;
• The fan does not work when needed.

Before changing the DTOZH on a VAZ 2114, you need to make sure that this is the cause of the problem. The malfunction may be caused by a broken fuse or a faulty fan.

Why the VAZ 2114 cooling fan does not work

The fan electric motor starts working only after the antifreeze temperature in the radiator reaches 100 degrees. To do this, it is connected to the on-board network via a thermal relay. If the coolant temperature is more than 90 degrees, and the fan does not turn on, then the reasons may be as follows:

• faulty fan fuse;
• break or poor contact in the fan motor power supply circuit;
• breakdown of the temperature sensor (cooling fan relay) VAZ 2114;
• poor contact on the temperature sensor connector;
• the fan itself is malfunctioning.

Before starting repairs, it is necessary to find out the cause of the malfunction.

How to find out the cause of the problem

You should start by checking fuse F4 (20A)kre, located on the left under the hood in the mounting block. This fuse also protects the horn power circuit. So, to check it, you can simply press the signal button. If it works, then the fuse is fixed. If not, then the latter should be replaced with a working one.

You can then continue by checking the fan motor itself. To do this, you need to unplug its connector and power the electric motor from the battery directly with wires. If the impeller starts to rotate, then the fan is working. Does the VAZ 2114 cooling fan not work? We continue to search for the cause. The next step is to check the condition of the fan sensor contacts and the integrity of the wires going both to the fan itself and to the sensor (VAZ 2114 cooling fan relay). The sensor is installed so that if it is de-energized, the control unit will start the electric cooling fan in forced operation mode. It's easy to check - just unplug its power connector and turn on the ignition. If the fan starts working, then the relay (sensor) needs to be replaced.

When should you change a cooling fan?

If the VAZ 2114 cooling fan does not turn on, it is not at all necessary to change the entire unit. You can try to repair it by replacing the brushes or bearings. If the cause of its breakdown is a short circuit or break in the winding of the electric motor, it will not be possible to repair the electric motor. In this case, you will have to replace it with a new one.