How to connect a coolant temperature gauge. How it works

Motors that operate under heavy load conditions (constant driving at high speeds, on the original engine, etc.).

As for the coolant temperature, it needs to be constantly monitored on any power unit, and accurate information will help you avoid. It is important to take into account that the standard sensor on many cars gives a very mediocre idea of ​​the degree of coolant heating.

Also, some models straight from the factory are completely devoid of an engine temperature indicator on the dashboard. In such cases (when there is no indicator or it shows only average values), drivers usually install a third-party engine temperature sensor (the digital analogue provides more accurate data compared to the standard solution). Let's look at this device in more detail.

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Engine temperature indicator: features

Let's start with a common situation. Let’s say that a car has a standard dial temperature indicator, but on such devices the scale may often not have calibrations, and the engine operating temperature needle in the middle position displays the real picture only conditionally.

At the same time, during operation, the driver notices that if the middle on the scale is the norm, then in various situations the needle can rise noticeably higher (for example, in traffic jams). It would seem that the motor is overheating.

Naturally, the movement of the car immediately stops, the owner hurries to turn off the engine and open the hood. However, upon inspection of the unit there is no. Then it is restarted and it turns out that it does not even turn on, although the device is operational.

When you feel the upper radiator pipe has an acceptable temperature, antifreeze does not “press” anywhere, the lower pipe may be completely cold, etc. Further checking of the coolant level and the condition of the coolant itself also shows that the fluid is normal, the interior heater (stove) is working normally, there are no air pockets in the system, and it is also working properly.

It also happens that if you let the engine cool completely, then start the engine and warm up the power unit to operating temperatures, this process can take a long time (judging by the indicator on the instrument panel). In this case, you can notice that although the needle has only risen a little, the radiator fan is already working, the lower radiator hose is warm, etc.

If we consider that everything is in order with the fan and cooling system, then the signs described above indicate a large error or problems with the engine temperature gauge. It is quite obvious that in such a situation it becomes difficult to understand when the engine reaches operating temperatures, whether the internal combustion engine is overheating, how long it is necessary to warm up the engine before driving, etc.

At the initial stage, many drivers begin to look for the cause. Some right away:

  • the standard temperature sensors on the engine and in the dashboard are checked;
  • wiring is ringing, etc.

In some cases, the problem can be solved, while in others it is still not possible to achieve correct operation of the standard temperature indicator. The fact is that often the culprit is control electronic modules that give a certain failure.

Replacing such modules is expensive and impractical. In this situation, a quality solution is a digital engine temperature indicator. Such an electronic sensor has a very reasonable cost (on average, from 15 to 55 USD), and is relatively easy to connect and install. The range of measured temperatures is also very wide (on average, from -65 to +240).

Please note that installation features may differ slightly on different types of internal combustion engines.

  1. The device is usually powered from the ignition switch.
  2. The digital panel is installed in a convenient place inside the car.
  3. As for the sensor itself, for accurate readings it must be immersed in coolant.

In other words, the device must be screwed into the block or cut into the pipe. To do this, some drivers replace the standard temperature sensor by simply screwing in a new one instead. However, this cannot be done on cars with for a number of reasons.

The fact is that the controller receives readings about the coolant temperature. In this case, it is necessary to separately install the digital indicator sensor, since it is strongly not recommended to remove the standard temperature sensor from the system.

Let's sum it up

Now a few words about practical operation. If the sensor is installed correctly, then the error in its readings will be minimal (no more than 1 degree Celsius). The presence of this device in the car allows you to constantly monitor the engine temperature and coolant.

It is worth noting that the indicator can also be used to check the operation of the thermostat and the declared thermostat temperature. Simply put, for example, the thermostat should open at a temperature of 85 degrees.

The engine first warms up to medium temperatures, then you can take hold of the radiator pipe. When it gets hot, this will indicate the thermostat is opening. In this case, the indicator should also display the declared opening temperature of the thermostat, that is, the same 85 degrees (corrected for error). Also among the advantages is the ability to accurately monitor the temperature of not only a hot, but also a cold engine.

Finally, we note that the most critical moment during installation can be considered the installation of the sensor itself on the engine. The device must be sealed. Also, increased demands are placed on the reliability of its fastening. It is important to avoid even the slightest leaks of antifreeze from the cooling system, which can occur precisely at the location where the digital engine temperature sensor is installed.

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Design, principle of operation and location of the engine temperature sensor. Distinctive features of different types of internal combustion engine temperature sensors.

  • The main signs by which you can determine problems with the DPKV crankshaft position sensor. Causes of failures, breakdowns, self-check.


  • A variety of signaling devices are used to monitor the operation of an internal combustion engine. We suggest considering how the coolant temperature sensor works, how it is checked and replaced if it is faulty.

    What it is

    A standard coolant sensor is a device that is used to measure the antifreeze present in an internal combustion engine. The recorded parameters of the sensor are returned using signals to the engine control unit, which in turn uses this data to adjust the required amount of fuel and a certain ignition angle.

    Without this thermometer, it is really difficult to understand when our engine is running at operating temperature, and the time to reach it depends on various factors, such as the conductivity that we practice in the first moments or the environmental factor, the outside temperature. It is for this reason that the precautionary principle must take precedence. It is better to heal ourselves with health, the sin of precaution, avoiding taking the engine of our car into high mode for a few minutes, than the sin of courage and turning the engine for too long.

    We don't have to stand idle to do this. The temperature of the coolant thermometer will not necessarily tell us that our car's engine has reached operating temperature. What is the difference between an oil thermometer and a coolant thermometer? Needless to say, it is important to differentiate between a coolant thermometer and a lubricant thermometer. The first is usually indicated by a pictogram of a thermometer in the water, and the second by a bottle of oil. On the instrument panel, in an additional console with three meters, we find the lubricant temperature, the turbocharger pressure and the pressure in the lubricant circuit.

    In some car models, the alarm can be used to switch to an electric ventilation cooling system. Let's say this is how the car coolant temperature sensor works in the VAZ-1117 (and number 1119) Lada Kalina, Lada Priora and Granta, Lanos, Toyota Camry (Toyota).

    Photo - coolant temperature sensor VAZ 2010

    These meters are especially important in a sports car, where you understand that your engine will have to respond to the demands of heavy use. Its absence in other versions, less powerful and in other cars, does not respond to any other aspect, but to the fact that manufacturers believe that they are not relevant to their customers. And in this case they consider it preferable to keep their installation rather than saving, but above all to show us a simpler and clearer instrument panel.

    Excessive coolant temperature can indicate a problem in the radiator or lack of coolant, a frequency that we must address as soon as possible to avoid serious damage. Just because the coolant temperature has reached what we consider normal temperatures does not necessarily mean that the engine lubricant has reached operating temperature. This is why we think having this indicator is so important.

    On many foreign cars, the device readings are also displayed on the dashboard. For example, in Volkswagen Golf, Subaru, Mazda, Opel Vectra and Passat, BMW, Ford Focus, Daewoo Nexia. , Fiat (Fiat), Audi (Audi) and others.

    As the sensor temperature is measured, its resistance level may change. Exists two kinds such sensors depending on changes in resistance:

    Why is it so important that we do not neglect oil changes, and that our precaution increases with the demands of use? In the flow of engine operating temperature, it is no wonder why it is very important to be very careful and respect the maintenance periods of our car. But we must not forget that the performance of this lubricant, and therefore its ability to protect those components that are subject to friction, not only decreases with cold, but also with use, weather, climatology or even the demands of what we make of our car.

    1. Sensors with negative temperature coefficient work on the principle: internal resistance decreases as temperature increases and vice versa;
    2. Positive temperature coefficient sensors. As the temperature rises, they increase resistance.

    Almost all cars have warning lights with a negative coefficient. Negative coolant temperature sensors are available in Gazelle, GAZ, MAZ, KamAZ, Mercedes, Nissan, Niva, Mitsubishi, OKA, Peugeot, Volvo, Renault Logan, OPEL Astra, Geely, ZMZ.

    Most of the time, the goal that leads to installing air conditioning is to provide a person with an environment more conducive to their well-being. On the other hand, this is an effective way to protect against infections and air pollution from large populated areas in confined spaces. It helps in the therapeutic treatment of many diseases; in industries, is a factor contributing to increased production due to higher incomes of workers located in more comfortable conditions.

    Air conditioning is an air treatment system that enters a specific location to provide specific temperature and humidity conditions. Treatments can be very different as the desired conditions vary depending on the location being fed. For example, a food storage warehouse requires different conditions than those required for a large commercial store, office, or movie theater screening room.

    Photo - temperature sensor

    Operating principle of the sensor

    The vehicle's control unit sends a regulated voltage (9 volts) directly to the coolant temperature gauge sensor. Depending on the drop in voltage at the contacts of the alarm, the resistance will drop, which will immediately be detected by the control unit.

    These different needs have resulted in numerous air conditioning systems varying in size, design and control equipment. However, the operating principle does not change significantly from one to another, from small to large. In the body of higher animals, and in particular in the human body, a series of chemical transformations occur through which absorbed food is converted into thermal and mechanical energy. This heat production depends on many factors. One of them is the constant exchange of heat between the body and the environment.

    In this case, the automotive computer or mechanical system will be able to calculate the engine temperature and then (using data from other devices) apply lookup tables to make adjustments to the engine drives, i.e. change the level and flow of fuel or the ignition timing.


    This change depends on the air conditions in which the body is immersed, depending on the temperature difference between the surface of the body and the surrounding environment, ventilation, etc. At temperatures close to the air, the heat generated by the body is not easily eliminated and the individual feels a sense of oppression. During these hot seasons, a very humid atmosphere saturated with water vapor is as harmful as excess heat, since it does not allow the evaporation of sweat. For this reason, the air conditioner must regulate not only the temperature, but also the amount of steam contained in the air.

    Photo - diagram of the coolant temperature sensor

    The resistance of the coolant sensor is highly dependent on external factors. This is the air temperature outside the car, various drive features. For the most correct operation of the alarm, you need to use coolant recommended for a certain time of year; it is expensive, but it prolongs the life of your car.

    In addition to temperature and humidity, there is a third factor that affects air quality: ventilation. These three are not independent; they interact in such a way that in conditioning a change in one must be compensated by a corresponding change in the other two so that the body is always in a state of sufficient comfort.

    There are several stages in a large air conditioning system. However, objects do not always include all the components that are combined into one box in small units. The air first enters a section where it is mixed with recirculated air from the environment itself, because only a certain proportion of fresh air is required. The mixed air then passes through a filtration section, which may have two stages. The first removes thick dust using a fibrous material, usually fiberglass, in the form of a screen that is replaced when dirty.

    Video: checking the engine temperature sensor

    Replacing the sensor

    To begin repairing the coolant sensor, you need to determine its location. Most often it is installed near the thermostat or radiator; in some cases, the on-board computer uses readings from both sensors or one of them, depending on the make and model of the car. For example, this is how the sensor is located in Renault, Chevrolet, Citroen, Skoda, Chery, KIA, Subaru Impreza.

    Then the second stage filter, which is usually an electrostatic type, removes smaller particles such as cigarette smoke. This filter uses high voltage to electrically charge dust particles, which are then attracted to a grid of charged plates of opposite polarity. As the air passes through two sets of pipes, it is temperature controlled. One of them circulates hot water or steam, and the other circulates cold water or refrigerant.

    A temperature sensor is installed in the ventilation area, which is set to the required value. The difference between the desired temperature and the ambient temperature automatically determines whether heating or cooling pipes will be used. The next step is an odor filter made from activated carbon, a substance that can absorb odor molecules in the air. The carbon must be periodically activated by heat to extract the absorbed material.

    There are several ways to help you find out that the sensor needs to be replaced. If all other systems in your car are working, then the dashboard will indicate a malfunction using a light signal. If the car has computer control, then the problem can be determined by deciphering the combination on the monitor.

    The desired humidity is generated by injecting steam or very fine droplets of water into the air using an evaporator. This is also monitored by a sensor located in the environment. In case of excessive humidity, the usual method is to cool the air and then, if necessary, reheat it in a temperature control stage, so that the humidity will condense in the refrigeration pipes.

    From the smallest to the largest system, the same principles are used. Small environment units contain a simple washable filter, refrigeration compressor and electric air heater. Larger environments use larger units, and often the cooling section is located outside the building.


    Photo - temperature sensor on the dashboard

    Depending on the year of manufacture of the car, as well as its brand, many car enthusiasts note an increase in engine fuel costs. But at the same time, you need to understand that diesel cannot be defined this way (UAZ, PAZ and others). If you have mechanics and not a computer control system, then here signals that you need to buy a new coolant temperature sensor:

    His invention will come to help the industry. During the hot summer months, the New York company had problems with printing work. The paper absorbed moisture from the air and expanded. Colors printed on damp days did not line up, creating washed out and unclear images.

    The carrier believed that he could remove moisture from the plant by cooling the air. To do this, he developed a machine that circulated air through artificially cooled ducts. This process, which controlled temperature and humidity, was the first example of air conditioning by a mechanical process. However, the textile industry became the first major market for air conditioners, which were soon used in many buildings and institutions in the paper, pharmaceutical, tobacco and commercial establishments.

    1. The car began to consume more fuel than usual;
    2. When the car starts and the engine reaches its maximum temperature, it stalls;
    3. There were problems starting up;
    4. Black smoke comes out of the muffler pipe.

    Let's look at how to replace the G62 coolant temperature sensor on a Kia Sportage with a 2-liter engine. Similar instructions will also be useful when repairing Acura, BMW, Buick, Chevrolet, Ford, Toyota, Volkswagen, VAZ 2110/2112 injector, Renault Grand Scenic and others.

    The first residential application was in a Minneapolis mansion, Currier designed special equipment for residences, larger and simpler than modern air conditioners. The system introduced additional moisture into the nursery for premature births, helping to reduce deaths from dehydration.

    In fact, air conditioning helped the film industry because during the summer months the frequency of movie theaters dropped a lot, and several rooms closed at that time. Also in the 1930s, Willis Quarry developed a system that made air conditioning more viable in skyscrapers.


    Photo - different coolant temperature sensors

    In this model, if the coolant sensor breaks down, alarm 117 is received, which indicates that further operation of the device is impossible and it is necessary to install a new alarm. In Chevrolet the number PO118 is a high signal. General scheme of work looks like that:

    In the 1950s, residential air conditioner models began to be mass-produced. The shares were sold within two weeks. Ten years later, these plants were no longer new and are still providing solutions in all parts of the world. Energy-efficient appliances will make a big difference in your light bill, especially in the summer when air conditioning accounts for a third of a home's energy consumption.

    Avoid excessive cold by properly adjusting the thermostat. Install the device in a place with good air circulation. Keep doors and windows tightly closed to prevent air from escaping into the environment. Clean the filters periodically. Dirty filters prevent free air circulation and make the device work harder.

    Advice from car enthusiasts on the forums: if for some reason you cannot immediately understand the coolant temperature sensor after a breakdown, then you can connect an additional one instead (such a connection may differ slightly in temperature from the main one).

    Protect the outside of the device from sunlight without blocking the ventilation grilles. Get used to turning off the air conditioner when you need to leave the room for a long time. Avoid solar heat in the environment by closing curtains and drapes. Do not block the air outlet of the appliance.

    When purchasing, look for models with programming features such as a timer. It is very important that the size of the unit chosen is appropriate to the size of the site and the thermal load, since if the installed unit is below the ambient thermal load, it must operate for longer periods of time, therefore consuming more energy, until it reaches a comfort temperature.

    The temperature indicator operates from a sensor. As a rule, coolant temperature sensors in a car do not require any maintenance. But often the motorist has doubts about the correctness of his testimony. A faulty temperature sensor can cause engine failure, the repair of which will cost a tidy sum. In this case, check the correctness of his readings.

    You will need

    tool kit, tester, hot water, 100 ohm resistor

    Posting sponsor P&G Articles on the topic "How to check the temperature gauge" How to increase the engine temperature How to replace the coolant temperature sensor Why the engine gets hot

    Instructions


    Disconnect the engine coolant temperature sensor connector while the engine is off. Take a 100 ohm resistor and connect it to the temperature sensor connector. After this, turn the key on and turn on the ignition. If the temperature gauge is working properly, the arrow on it should show 90? C. The engine must be cold when performing this work. If the arrow on the dashboard does not show anything, check the wiring leading to the temperature gauge. In the event that the wiring is intact and the indicator does not work, simply replace this device - that is the problem.

    If the gauge works normally, connect the connectors to the coolant temperature sensor. Start the engine and let it warm up completely. If the temperature gauge does not show anything, or its readings do not correspond to the normal engine temperature, the problem is in the sensor itself, replace it.

    There is another way to check the temperature gauge. Disconnect the negative terminal of the battery on the car. Drain the antifreeze from the engine so that it does not spill when unscrewing the sensor. The engine should not be hot. Slide the protective casing off the harness that goes to the sensor and disconnect it from the connector to which it was connected.

    Using a key, carefully loosen the sensor and then unscrew it from its socket. Take the tester and adjust it to ohmmeter mode. Connect one contact to the sensor terminal, and the second to its body. The tester should show a resistance of 700-800 ohms at room temperature. When the sensor is immersed in hot water, its resistance should decrease, and as the water cools, it should increase again. If this does not happen, the problem is in the sensor. If the sensor is intact, check the wiring and, if necessary, change the temperature gauge.

    How simple

    SPECIFICATIONS

    • Article: 9280

    Universal engine temperature indicator with diagnostic function

    The indicator is designed to display coolant temperature in digital form, as well as display and erase diagnostic codes that occur when malfunctions occur in the engine and transmission control system. The indicator is used in vehicles equipped with a CAN digital information bus.

    ATTENTION! The indicator does not work on VAG group cars (Volkswagen, Audi, Skoda, Seat).

    SPECIFICATIONS

    LIST OF SUPPORTED VEHICLES

    The list of cars will increase as tests are carried out.

    ATTENTION! The indicator does not work on VAG vehicles.

    CONNECTION METHOD TO THE CAR

    The coolant temperature is displayed on the indicator within a few seconds after the ignition is turned on. The indicator periodically sends a request to the CAN bus and updates the temperature readings.

    Diagnostics of the engine and gearbox occurs when the ignition is turned on; the indicator displays the number of stored errors in the EXX format, where XX is the number of errors. Next, error codes are displayed in a creeping line. The code consists of five characters: one letter and four numbers. Deciphering the codes can be found on the Internet. After all errors are displayed, the indicator will show the engine temperature.

    To erase codes from the car’s memory, you must turn off the ignition, then press the accelerator pedal to the maximum, turn on the ignition and wait for the “clr” error erasing notification to appear on the indicator. If the errors do not disappear, repeat the erasing procedure.


    For some reason, many car enthusiasts are simply not satisfied with the usual dial indicator of engine temperature on the car dashboard. This is mainly due to the fact that such sensors, in most cases, show inaccurate and sometimes incorrect data. In today's article we will talk about a possible solution to this problem, and the solution will be to install a new sensor with a digital temperature indicator.

    The reason why dial indicators show incorrect data is usually that their operating range, which is approximately 300-400 ohms, has some error of up to 50 ohms. Because of this, inaccurate data is displayed. The digital indicator, in turn, does not have any errors in the data output and is able to more accurately determine the engine temperature and transmit its value to the dial. In addition, such indicators are equipped with an additional number of useful functions, such as:

    Turning on the fan on the radiator when the engine temperature reaches 910C and turning it off at 880C;
    Application of a sound signal, something in the form of an alarm, when the temperature reaches 990C and turns it off at 980C;
    Turning on an additional signal at critical 1100C;

    In a sense, we can say that this indicator not only measures the exact temperature of the engine, but also has (albeit reduced) functionality of on-board computers.





    This device is configured in such a way that the switching temperature of the fan sensor 2103-07, the range of which is narrowed on both sides by 10C. This is needed to more accurately measure the temperature in the engine block, and not on the radiator.
    The temperature sensor itself is placed in the housing of a standard, old temperature sensor TM106. Before placement, everything is treated with thermal paste and a connector is made so that if the temperature sensor is defective or goes out of service, it can be replaced without deforming the case itself.

    If you do not have the sensor firmware, the diagram will not give you any useful information. The firmware for the above circuit can be found at this link. Well, this option will help you connect several thermometers at once, as well as use one of the PIC devices to choose from.


    In our case, there was a VAZ 2110 car, which did not have an additional hole for the sensor dial, so we cut it out ourselves. Once the dial is installed, it may be that the brightness of the dial exceeds the brightness of the other instruments on the panel, so we applied a darkening surface to the dial, which reduced its brightness a little.
    This small tuning of your car will provide you with more accurate monitoring of the car’s engine temperature parameters, and will also notify you in time about overheating.