Of course, the most common cause of an unusual reading on your car's temperature gauge is an issue with engine temperature. However, there are other reasons, for example:
- Poor sending device temperature (second most common cause)
- Problem in the electrical circuit of the temperature sensor
- Malfunction in the control circuit from the car computer (depending on the car model)
- Bad sensor
Any of these conditions could cause the temperature sensor to:
- Show either low temperature value
- Either high
- Fluctuate – shows sometimes big, sometimes small, or generally jumps
But your engine heat gauge won't tell you what kind of problem you're dealing with. If you don't notice any obvious symptoms under the hood or the problem doesn't cause your check engine light to come on, you'll need to do a little diagnostic work to figure out what's going on.
Why does the engine temperature drop while driving?
But the problem has not gone away, and everything here has even become warmer, but the problem remains. Further interesting, no matter where I went, everyone said the same thing - thermostat!
At speed, the engine temperature drops. Note that a decrease in the temperature of the internal combustion engine while driving can also occur naturally and not be a consequence of any malfunction.
This usually manifests itself in the cold season, that is, during frosts. On many cars, when driving on the highway, the engine temperature drops, since the engine temperature drops when the Chevrolet Lacetti is driving and the front part of the engine compartment is open to blowing by oncoming air. This mode can be considered the most economical, that is, the minimum amount of fuel burns in the cylinders.
For ease of understanding, the lower the speed and the less fuel burned in the cylinders, the less heat the engine has.
Do not forget that in winter the driver constantly uses the stove in the cabin, which additionally takes away heat. This phenomenon is typical for entry-level and middle-class cars, which are often equipped with low-volume internal combustion engines and do not have additional hood insulation.
What is the operating temperature of the Lacetti 1.6?
It is also worth noting that many diesel engines do not heat up well at idle and can cool down noticeably while driving. It is especially noticeable on small cars and models equipped with medium-sized engines.
The situation is also typical for diesel engines, which not only do not warm up well at idle, but also cool down quickly when driving with insufficient intensity. The car heater has a special radiator, which is included in the general operating circuit of the cooling system. When the driver turns on the interior heating, antifreeze passes through it, giving off some of the heat.
Engine temperature drops when driving
The amount that will be given depends on the set temperature of the heater and its operating mode. The higher these indicators are, the more the interior of the car will heat up. If the engine operates at low speeds, and is also used in winter, there may simply not be enough heat to fully warm up the coolant.
Is it possible to slow down the drop in engine temperature when driving a Chevrolet Lacetti engine in cold weather? In the past, different materials were used to create engine insulation. These are the different felt fabrics available in circulation. But such decisions did not keep the heat for long. Modern thermal insulating car blankets are now used. Their composition prevents ignition, which has a positive effect on the safety of vehicle operation.
Also, numerous engine warm-ups will not be required.
This will save time and fuel. When the weather conditions are too harsh, such techniques will be able to retain heat in a short period of time. It is possible to use special covers for the radiator.
Its lower part, together with the pipe, must be thermally insulated in order to maintain a stable temperature of the running engine.
Actions to prepare the cooling system for winter The winter period of operation is difficult for all vehicle owners. Preparatory work will help you be fully prepared. Discussion closed by moderator Lexona The thermostat is located at the coolant outlet from the head, the coolant temperature is maximum here.
5) Dirty radiator
If your car has driven more than 80 thousand km, then most likely the cooling radiator is very dirty, which can also cause the engine to overheat.
In order to avoid this, it is necessary to flush the radiator every year. It is advisable that, along with cleaning the radiator, the coolant itself is changed. Despite the fact that the manufacturer itself recommends changing antifreeze every 3 years, we, for our part, strongly recommend changing this coolant every year.
In conclusion, dear readers, we would like to once again remind all car enthusiasts that in addition to regularly checking the entire cooling system (especially before a long trip), it is necessary to periodically conduct a complete diagnostic of the operation of all the most important systems of the car. Don't forget to regularly check the oil level in your car engine. Remember that by maintaining the engine oil level at optimal values, you reduce the load on the engine itself and thereby prevent unnecessary overheating (heating) of the engine in advance.
The lower the load on the engine, the longer the service life of the vehicle's power unit. Good luck to you friends!
An internal combustion engine is a kind of furnace in which, during the combustion of working mixtures, the temperature in the cylinders reaches 2000 °C and higher. At such temperatures, the metal begins to lose its strength characteristics, which can lead to problems associated with the operation of the engine, or, in general, send it to the cemetery. To avoid such consequences, cars are equipped with a cooling system that limits the temperature limits of the engine, thereby ensuring the correct conditions for its operation. A car engine is a metal mechanism, which, unfortunately, is not perfect. And various types of failures in its operation are still present. The most famous are when the engine gets very hot, or, conversely, takes a long time to warm up. What causes this?
Hydrodynamic and boundary lubrication: what are the differences?
The hydrodynamic process occurs as follows: the oil fluid is pumped through a pump and, passing through a heat exchanger, reaches the crankshaft through the filtration system. These actions are performed under pressure, and if the engine operating temperature is normal, the lubricant travels all the way in a fraction of a second. At the beginning of rotation, a so-called oil wedge is created. It is formed due to the fact that lubricating fluid under strong pressure enters the gap between the crankshaft journals and the bearings.
Auto information panel
If the engine is started in the cold season, exactly the same processes occur in it. But due to its high viscosity, the oil cannot pass through the filter. As a result, the lubricating fluid passes through the bypass valve, causing the product to be partially unfiltered. However, this situation does not affect the normal operation of the engine. The design features of the motor ensure the passage of oxol to its parts, even if the filter blocks the flow of liquid. As the temperature rises, the viscosity decreases and the lubricant again begins to pass through the filter system without affecting the bypass valve.
A process called “boundary lubrication” involves constantly renewing the oil. In this case, a liquid containing anti-wear additives is used. This way, all engine parts that the oxol passes through without pressure are lubricated.
The lubricant is renewed by spraying through nozzles or by splashing. New generation engines have special cooling nozzles, which reduces the piston temperature. Boundary lubrication allows you to constantly remove used oil from parts of the mechanism and bring it a new portion.
How to find out why your car is overheating.
Engine overheating is the worst thing that can happen to us on the road. Due to high temperatures, the car engine may fail and you will then have to go to a technical center for expensive repairs. As a rule, such overheating of the car (of course the engine) mainly happens when you get into a traffic jam. At this moment, any driver (or almost any) prays that the flow of traffic from cars does not stop and at least continues to move a little. The point is this: while driving, your engine receives additional air flow and thereby is constantly cooled, which means it does not overheat. So what are the main reasons for engine overheating and how can you and I avoid it?
There are several main reasons why the engine temperature begins to rise (creep to the top) and, if the car is not turned off, it will overheat.
Basic faults
If the sensor is working correctly, the needle moves smoothly, but if there is a problem, the movements will be sharp and jerky. With such work, not only can it be impossible to correctly assess the temperature position, but it can also cause damage to the engine and the entire system. Breakdowns can be different and happen in several places at once, but most often motorists encounter the following reasons:
- Thermostat failure.
- Malfunctions in the operation of the coolant temperature sensor.
- Malfunction of the indicator itself and the sensor needle.
- Short circuit in the electrical board.
These causes are arranged according to frequency of occurrence, so we advise you to make the same diagnosis. If it is possible to turn to a specialist for help, this will significantly reduce the time it takes to find and eliminate the cause.
Thermostat failure
The problem with the thermostat is the most common, and all because of the poor protection of this part. The fact is that it can break even on a new car. Some people talk about randomness, and others about the conditions of use. One way or another, it is worth understanding how this system works and how to check its serviceability.
Often such breakdowns occur at low temperatures, but can and will also occur in the opposite conditions (heat waves). When the car starts and the engine warms up, the sensor needle immediately jumps to the correct value, and then the thermostat opens. The coolant begins its movement through all components through the pipes, however, if the thermostat is broken, it shorts out and blocks further passage for the liquid. There are cases of complete closure of the thermostat valve, and there are cases of partial closure, but in both cases, prolonged operation of the engine will lead to overheating and the engine temperature sensor will jump.
To independently diagnose, you should check the thermal state of the supply pipes. In cases where the thermostat is stuck, the lower pipe will be colder than the top. This will prevent the coolant from making a large circle and the engine from starting to operate normally.
Coolant temperature sensor
The next most common breakdown is the coolant temperature sensor. Sometimes it may happen that a contact in it comes loose and data will not flow or will come with breaks in the circuit. Because of this, the needle will twitch, because for it the indicators jump sharply from the working value to zero. There is also a possibility that the sensor itself is broken and it simply cannot record data properly.
When each sensor is detected, you need to make sure that it is intact, as well as that the contacts are properly connected. To fix it, two people will be needed: one moves the contact, and the other monitors the arrow readings. If the arrow reacts to actions and starts jumping, then the problem is with this sensor.
Arrow and temperature sensor
In cases where the thermostat and the thermal sensor connection contact are in order, it is worth paying attention to the sensor indicator itself, there may be malfunctions in the integrity of these parts. In order to identify a breakdown, you need to have certain knowledge about the resistance and structure of this electrical mechanism
Because perhaps it is the poor condition of the sensor that makes the needle jump like crazy.
This knowledge can be studied independently on the Internet or in specialized books, where all operations and indicators are carefully described. But the best outcome, of course, would be to contact a specialist who already knows about all the intricacies of the sensor design.
Electrical board of instrument panel
If everything works well, but the temperature sensor still jumps, then all that remains is to disassemble the instrument panel and check the electrical board. If the soldering is broken or done poorly, it will lead to problems like this. If you plan to fix this problem yourself, we recommend taking a soldering iron with a thin rod and low power so as not to damage the board and adjacent parts.
It is also worth paying special attention to the output mass and resistors. And if you can’t do this kind of work yourself, then contact a specialist who will do it quickly and without errors.
Prevent car computer damage
If your car computer acts as the interface between the sending device and the temperature sensor or warning light, turn the ignition switch off when disconnecting the wires from the sending device, warning light or temperature indicator. This is necessary to prevent damage to the computer from induced voltage. Refer to your vehicle's repair manual.
If you suspect it is faulty, the temperature sender is most likely the culprit.
The temperature needle drops. Why?
The most common problems are when the temperature of the unit increases uncontrollably, reaching critical values. The cause of overheating is a jammed thermostat, which does not allow the coolant to pass through the radiator. The heated antifreeze continues to circulate in a small circle until it boils.
The opposite situation often occurs when the engine temperature gauge drops while driving. Why? The point, again, is the quality of operation of the mentioned valve. If the thermostat cannot close all the way, allowing the fluid to continuously circulate in a large circle, the engine will not warm up to its operating temperature.
Sometimes the thermostat gets stuck after the engine has warmed up. When this happens, the driver may notice that the engine temperature drops while driving, although it should be maintained at a consistently even, operating level.
Sometimes the temperature regime changes abruptly, sometimes increases, sometimes decreases sharply. This means that the valve periodically jams, and the driver will notice a situation where the temperature arrow periodically drops.
Increased engine wear is the most unpleasant cause of heating
If you've checked all the above options for engine overheating problems, but none of them apply to your situation, it's time to turn to the most unpleasant test. The operating temperature of the power unit increases greatly in the last stages of its life. By the way, this is one of the indicators of a problematic car that you should not buy second-hand. If the engine runs at a temperature 2-3 degrees above the optimal temperature, refuse to buy such a car. The check in this case will be quite simple. You need to complete these simple tasks:
- take the car to a service center for repair of engines and other important components of the car;
- conduct computer diagnostics aimed at identifying possible problems with the unit;
- carry out a technical and mechanical check of the condition of the unit, which will give preliminary answers;
- if specialists suspect possible increased wear, a thorough examination of the cylinder block takes place;
- after this procedure, it will be completely clear whether a major overhaul or even replacement of the engine will have to be performed;
- At the service, you can perform all the work necessary for the normal functioning of the unit.
On some cars, the engines are disposable. This means that the walls of the cylinder block are very thin, they do not allow for major repairs and the installation of larger pistons. In this case, it will be much cheaper to buy a contract engine from Japan or Germany, install it and drive with such a unit in a semi-legal legal sphere. You can look for an engine at a disassembly site or buy a new unit at a spare parts store. Then there will be no special problems with registration. But it will be incredibly expensive. In other power units, a major overhaul is possible, which will solve the problem for several tens of thousands of kilometers. We invite you to watch a video with possible causes of overheating in a classic engine:
Selecting and purchasing a thermostat for Kalina
Here I will not discuss what is better to buy and which thermostat to choose. Given the disgusting quality of most spare parts in stores, I do not consider it necessary to waste time on dubious tests and comparisons of parts from different manufacturers. I’ll just say one thing: I chose a factory-made thermoelement, that is, the element itself, and not the thermostat assembled with the housing.
If you do not have any problems with the body of this part, the thread for the sensor and thermoelement are in place, then you should not overpay 500 rubles on top. Feel free to buy an element that costs about 500 rubles for Kalina - the price of the factory one. When replacing it, there are much fewer problems with it; you only need a hexagon and a pair of heads with a knob for unscrewing the clamp screws.
As for the result of the work done, as expected, now there are no problems with the cooling system. The engine began to heat up much faster, and the operating temperature remains stable at 90 °C, and the on-board computer shows exactly these numbers.
As for the operation of the heater, it goes without saying that the higher the coolant temperature, the hotter it will be inside the car. Now it has become even warmer in my Kalina, which is what was required from this repair.
During the operation of the car, its owner has to deal with various malfunctions. As a rule, breakdowns that are somehow related to the operation of the power unit are of particular concern.
Even for beginners, it is not news that the car’s engine must warm up to its normal operating temperature, which is 90 degrees. This temperature regime is optimal.
Checking the temperature sending unit
When you suspect something is wrong with the temperature sensor, you should first check the temperature sending unit, which is more accessible and more prone to failure.
You can check the resistance or voltage of the transmitting device using a digital multimeter (DMM).
Older car models use a single temperature sensor. Newer car models connect to an electronic control unit (ECU) or car computer, which then sends information to the temperature sensor. Other car models, especially Asian ones, use two temperature sending units, one connected to the computer and the other to the temperature sensor.
You may need to consult the vehicle repair manual for your specific model to locate components and identify wires and terminal connections. If you don't have a repair manual, you can buy a relatively inexpensive copy from Amazon. Haynes manuals provide step-by-step instructions for many troubleshooting, repair and component replacement projects you can do at home.
Testing the resistance of the sending device:
- Locate the temperature sending unit. Typically the block is located next to the thermostat housing, which connects to the upper radiator hose on the engine's cylinder head.
- Disconnect the electrical connector of the sending unit.
- Measure the resistance of the device with a cold engine using an ohmmeter. The resistance must be high.
- Measure the resistance of the device when the engine is hot. Resistance should be low.
- Compare your readings to the specifications in your vehicle's repair manual. If the sending device specifications are correct, proceed to the next steps.
Reference voltage testing:
- Turn off the ignition.
- Disconnect the wiring harness from the temperature sensor.
- Connect the red lead of your voltmeter to the metal reference wire terminal.
- Connect the black lead of the voltmeter to the negative (-) terminal of the battery.
- Turn the ignition key to the "On" position, but do not start the engine.
You should have a 5 or 12 volt reference signal. If not, check this wire for damage. If the wire comes from the computer and the wire appears to be in good condition, the computer may be faulty. Refer to your vehicle's repair manual.
Checking the output voltage of the transmitting device:
On some models, you will be able to back probe the sending device's signal wire using your voltmeter.
- Connect the red wire of the meter to the signal wire of the sending device (refer to the repair manual if necessary).
- Connect the black lead of the meter to the engine ground or negative (-) battery terminal.
- With a cold engine, set the parking brake, start the engine and let it idle.
- Observe the voltage readings as the engine warms up. Your readings may be similar to those in the following table, with the reference voltage being 5 volts for the computer sending device (some models may use a 12 volt reference).
| temperature | voltage |
| 110F (43.3 C) | 4,2 |
| 140F (60C) | 3,6 |
| 180F (82.2 C) | 2,8 |
| 210F (98.8 C) | 2,2 |
| 230F (110C) | 1,8 |
| 250F (121 C) | 1.4 |
A sending unit with poor temperature can also cause the car's computer to adjust the fuel system based on incorrect data. You can see for example:
- Black smoke
- Difficult starting on a warm engine
- Increased emissions
Why does the engine not warm up to operating temperature?
If the car engine does not warm up to 90 degrees during operation, it is necessary to urgently check its cooling system; most often the problem is related to it. The following faults can be identified that can lead to this kind of problem:
- Thermostat is not working properly. In a car engine, the thermostat is responsible for switching the direction of coolant flow. When the engine just starts, the coolant in it moves in a small circle, warming the engine up to operating temperature. When the engine temperature reaches approximately 90 degrees, the thermostat switches the direction of coolant flow to a large circle. If the thermostat gets stuck and does not fulfill its direct duty of switching the direction of coolant flow, this can lead to both overheating and overcooling of the engine. Accordingly, you need to check the thermostat, and if it is faulty, you will need to replace it with a new one;
- Air is sucked in through the pipes. If the pipes are not tightened properly, additional air from the atmosphere may enter the system. Most often, if there is a similar problem, you can see traces of coolant on the pipes, which partially flows through them. In such a situation, you need to tighten the clamps better and check the pipes for cracks and tightness;
- Error in the operation of the coolant temperature sensor. If the sensor provides incorrect information, the driver may be misled by the information displayed on the instrument panel. The scale will indicate that the engine is not warming up enough, although in fact this may not be the case. To avoid the possibility of this type of problem, you need to check the coolant temperature sensor and replace it if there are deviations from optimal results.
Above are the three most common reasons why the engine does not warm up to operating temperature (or the driver believes that the engine is not warm enough). In 95% of cases, the problem is related to the thermostat, which is recommended to be changed every 3 years or every 50 thousand kilometers.
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2) Electric cooling fan failed
If your car has an electric cooling fan and it fails (no rotation when the engine is hot), this can also lead to overheating of the car (engine).
The point here is this: the electric cooling fan transfers cold air from the street to the engine, which passes through the cooling radiator. The fan cools the engine while your car is moving at low speed, thereby helping the engine cool.
If while driving the car you see that the engine temperature has begun to rise and move towards the red danger zone, then please stop the car, then open the hood and check whether the cooling fan is working.(?) If the fan does not spin, then you It is necessary to find out on the spot the cause of the malfunction, which may be the following:
— Poor contact feeding the fan
In order to check the contact of the cooling fan, it is necessary to remove the wiring harness that powers the fan. Using two wires, power the fan directly from the battery. If the cause of the fan malfunction is the wiring harness, the cooling fan will work.
If your car does not have a radiator sensor, then this test method may not be suitable for you. Then, to detect a malfunction, you need to remove the electrical connector from the fan, and then you can close the contacts of the connector of the fan itself. If it is working properly, the fan will work.
— The fan switch sensor is faulty
Many, and especially modern cars, have a temperature sensor that turns on the cooling fan. This happens after the coolant temperature has reached its certain temperature.
In order to check the serviceability of the sensor, it is also necessary to remove the wiring harness feeding the fan and close the fan contacts. If the fan is in good condition, it will start working.
I have contact
As electricians say, there can only be two faults: there is no contact where needed, or there is contact where it is not needed. This rule also applies in the situation under consideration. The arrow will jump if the joints are oxidized or weakened. Moreover, most often this happens when additional consumers are connected: low beam, headlights, etc.
As mentioned above, the first thing to do when diagnosing DTOZH is to check the contact in the connector. Returning to the previous section, the following should be added: if the sensor malfunctions, the readings fluctuate within the same range, and if they change chaotically, the wiring may be damaged. How important the negative contact is - the mass - will be confirmed by one case described by a forum participant.
The gauge needle sometimes jumped to 130°C. After stopping the engine, it showed the correct result - 90°. The voltage at the battery terminals when the engine was not running was about 12.5 V, and after starting it rose to 13.7.
After a year and a half of unsuccessfully searching for the cause, replacing the battery, alternator and two temperature sensors, I came across one grandpa who installed an additional ground wire from the engine to the body, and the problem was solved.
Let's start with theory
The car moves due to the energy obtained from the combustion of gases in the air-fuel mixture in the cylindrical engine block. Only 10% is spent on this, and the remaining 90% is used for useful life processes of the vehicle and heat generation. Among the important components:
- Traffic fumes.
- Heating the coolant.
- Incomplete combustion of fuel.
- Technical losses.
Even at the production stage, the carburetor engine is sharpened to a coolant temperature of 80-90 degrees. The thermostat is usually closed to this temperature and circulates the liquid in a small circle. And only when the antifreeze reaches the specified temperature does the unit open completely. When it fails, functional errors are observed - insufficiently heated liquid enters the main thermal circuit. And this is fraught with slower warming up of the engine and deterioration in the efficiency of the entire heating system. Now let's look at why the temperature inside the engine drops when the stove starts and the engine starts moving.
Principle of operation
Coolant enters the radiator through the thermostat. This is a large circle of fluid circulation. The thermostat usually opens at a temperature of 100 degrees Celsius. If the temperature has not reached this limit, then the liquid moves in a small circle. A thermostat malfunction is manifested by improper opening of the valves.
When the thermostat is closed, the engine overheats, and a constantly open one leads to low temperatures, since the liquid will only flow in a large circle.
Due to irregular changes of antifreeze or antifreeze, use of running water or mixing of coolants, various deposits in the form of scale may accumulate in the system. In this case, the thermostat will inevitably jam in one of its positions.
Long warm-up of the engine with LPG
This is also an important point that affects the engine warm-up time.
When installing HBO, we interfere with the engine cooling system by inserting a gearbox into it, which now also needs to be warmed up.
Therefore, if your car has HBO installed, then you can safely add a minute or two to the warm-up time.
I clearly demonstrated this point in the video below.
Performance test
To check the thermal sensor, it will have to be removed from the car. To do this, follow these steps:
- Allow the engine to cool to 40-50 °C to avoid burning your hands during operation. Partially or completely drain the antifreeze from the cooling system.
- Disconnect the battery from the on-board power supply by removing the negative cable.
- Disconnect the block with wires from the thermoelement.
- Unscrew the part using a wrench of the appropriate size.
If the device is installed at the top point of the system, then it is not necessary to empty it entirely; it is enough to drain a third of the liquid into the container. All antifreeze must be drained when the thermocouple is located at the bottom of the radiator.
To carry out the tests you will need:
- a multimeter or other device capable of measuring circuit resistance;
- a small container for water (you can use a regular glass);
- thermometer with a scale up to 100 °C.
A thermometer is essential if you want to make accurate resistance measurements by referring to the reference chart for your vehicle. When there is no table, the serviceability of the part is checked without a thermometer according to its operating principle: the hotter the water in the glass, the lower the resistance at the contacts should be.
If the multimeter shows a certain resistance, then immerse the thermocouple in a glass of cold water and record the readings. Then add hot water and watch the resistance change, it should decrease. If there are no changes, purchase and install a new temperature sensor.
If the tests were successful and the device changes resistance when heating the water, then it is worth checking the connecting wires and cleaning the contacts. Little things like this often cause major problems.
When the engine takes a long time to warm up
In winter, with the onset of frost, car owners have one experience replaced by another, and the latter is much more troublesome than the usual overheating of the engine. When it’s -20 -30 °C in the morning and the engine takes a long time to warm up, you can’t help but remember the beautiful, warm days. Well, it’s okay that the engine warms up a little, the main thing is that the fingers straighten! But the heat is still far away, and problems with the engine are already happening. In winter, there are three reasons why a diesel engine heats up slowly:
- The thermostat is made;
- An air lock has appeared in the coolant system;
- The motor is not insulated enough.
Checking the thermostat
Designed to be sensitive to changes in temperature, regardless of changes in pressure in the coolant system, the service thermostat will limit the circulation of antifreeze to a small circuit through the cooling jacket of the block and cylinder head. As the temperature difference between the environment and the engine increases, the thermostat smoothly opens the coolant supply from the main radiator to the engine. This is exactly what happens in the opposite case. Thanks to this, the temperature limits of engine operation are maintained and limited, and the vehicle interior is heated.
Causes of malfunction
Arrow stuck on dashboard
It’s probably no secret to anyone that the arrows hanging on the dashboard are inextricably linked with the electrical circuits in the car. To troubleshoot the problem, the car enthusiast will need some knowledge of auto electrics, as well as design knowledge of the VAZ-2114.
As practice shows, most motorists, when such a breakdown occurs, turn to a car service center, but this problem can be eliminated on their own. But, first of all, it is necessary to find the immediate cause of the effect.
What are the options?
So, let's look at the possible options for the engine temperature indicator arrow to hang on the dashboard:
- The magnetic motor of the pointer drive is broken.
- Breaks and disturbances in the operation of the electrical circuits of the dashboard.
- Short circuit in the circuit board of the device itself.
- Freeze related to temperature sensor.
- Problems with the ECU.
Elimination methods
Once the root causes have been identified, you can move directly to methods to resolve the problem.
So, now that the motorist is fully armed, you can proceed directly to the diagnostic and repair process.
The magnetic motor of the arrow drive is broken
The process of repairing and disassembling the dashboard
The most common problem with the arrow hanging or not responding on the instrument panel is a breakdown of the drive motor. To diagnose this device, you need to use a multimeter to close the winding contacts to an electrical circuit or resistance.
To troubleshoot the problem, of course, it is recommended to contact an auto electrician, who will do everything quickly and efficiently, but if the car enthusiast has the necessary skills and abilities in repairing such equipment, then he will be able to independently replace the motor and solder the necessary contacts.
We recommend: Why and how does oil get into antifreeze?
Breaks and disturbances in the operation of the electrical circuits of the dashboard
Wiring related fault determination
Another common reason for a stuck sensor is a break in the electrical circuit from the coolant sensor to the dashboard. It is quite simple to identify this; you need to remove the ground wire from the sensor and connect it to any other “minus” so that the electrical circuit is closed.
If the wire is not broken, then the arrow will begin to move; if not, then according to the electrical diagram it is necessary to find the wire in which the break occurred and eliminate the fault. As practice shows, motorists do not change the wire, but simply connect and insulate the contacts at the break point.
Short circuit in the board of the device itself
Detection of short circuits on the instrument board
But, in this case, an indirect sign is that nearby signs also fail. So, the tachometer and other indicators may not show. Here, troubleshooting is to replace the instrument panel assembly.
Freeze due to temperature sensor
Temperature sensor location
A frozen temperature arrow on the instrument panel will be associated with a faulty temperature sensor. So, its diagnosis can be carried out by analogy with a wiring break, or checked using a tester. If, as a result of diagnostic operations, it turns out that the coolant sensor is faulty, it must be replaced.
Problems with the computer
The process of identifying ECU errors and eliminating them
In this case, using the appropriate cable, you need to connect to the “brains” of the car and see if there are any errors. If there are too many of them, then you need to reset them.
Of course, if this procedure does not help, then it is recommended to reset the software. It is recommended to trust this procedure to professionals who will not only fix the problem, but also set the motor to optimal operating mode.
Thermostat
The main task of the thermostat is to direct coolant through two cooling circuits depending on its temperature. When the engine is cold, the thermostat is closed, but when it warms up it opens, releasing coolant through a large circuit.
If the thermostat is stuck open, the coolant warms up very slowly and the engine temperature gauge shows insufficient heating. It can become jammed as a result of a foreign object getting under the valve. This could be a piece of scale, sealant, or scale. Also, the reason for its failure may be simple wear and tear. In any case, this part must be replaced.
How to check the coolant temperature sensor?
There are two ways to check the functionality of the DTOZh: by dismantling it or directly on the car. Let's take a closer look at them.
Checking the removed sensor
First, the coolant temperature sensor must be removed. To do this, you only need a wrench of the appropriate size. Then for diagnosis you will need water, a boiler or electric kettle, an electronic multimeter that can measure resistance and a thermometer.
We pour water into the container we are using and place the sensor and thermometer in it and heat it up. After this, we measure the resistance at intervals of every 5 °C. The output will be a table with data that needs to be compared with those indicated in the technical documentation of your car. You can also find a similar table on the Internet.
This method, of course, is not without errors, but they are not critical and depend entirely on the diagnostic conditions, as well as on the characteristics of the sensor itself.
You can check the performance of the DTOZH without a thermometer. To do this, the sensor is immersed in boiling water, and then its resistance is measured using a multimeter. If the part is in good condition, then the resistance value will be as close as possible to what is indicated in the table. Small discrepancies in this case are acceptable.
