Things you need to know about car sensors

Advancement of technology has made life easy, even in automotive, as they now feature sensors that send information about the condition of the vehicle. The technology has involved artificial intelligence and mobile connectivity. Sensors are now one of the essential device vehicles must include on modern designs.

Modern vehicles are now so convenient that the internet is now accessible, relaxation while the vehicle is on self-driving mode, effective communication etc. All these are part of the functional aspect of a sensor device. With the component, the engine has the ability and intelligence to know and make changes when necessary.

various types of car sensors

Today we’ll get to know the definition, functions, components, diagram, types, working principle, and symptoms of bad or failing sensors.

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What is a car sensor?

A car sensor is an intelligent device that monitors the condition of a vehicle and sends information to the user to know when changes should be made. In some situation, it automatically makes changes to the engine. The device controls a different aspect of a vehicle, which include temperature, coolant system, oil pressure, emission levels, etc.

Automobile sensors are so smart that they accept a range of values, examine them ideally and determine the suitable condition. If the component that features the sensor is faulty, it sends warning information to the user.

The sensor is always set to notice changes with the vehicle parts. This means sensors are always working as far the engine is running. The early design of sensor works only on the engine, but it’s now advance that it controls every part of the vehicle, starting from the temperature control inside the engine to the least electrical component of a car.

Functions of car sensors

With the above explanation am sure you can derive some functions of car sensors. Since they are different types, powering various applications and functional system in a vehicle. The functions are so broad.

Nevertheless, the primary functions of all term called sensors in automobile still remain the same on their various application. The information about the application they monitor to the computer (ECU) which work with algorithms. The algorithms already contain the various conditions that the device can experience, so when such occurs the computer could make changes to the correct situation. Whenever the computer could not make the adjustment, it sends warning information to the driver.

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Diagram of automobile sensors:

Types of car sensors:

Below are the various types of sensor used in an automobile to take care of different aspects:

Mass airflow sensor:

The airflow types of sensors are used to determine the volume and density of air taken by the engine. These sensors are used inside the engine where combustion occurs, it performs its operation by calculation. The device ensures the right amount of fuel and air is taken for a mixture so the engine can meet its optimal driving conditions. if the sensor fails the car may consume more fuel and sometimes it may stall.

Engine speed sensor:

The sensor for the engine speed controls and monitor the spinning speed of the crankshaft. this is to say the sensor is mounted to the crankshaft. if you understand the working of an engine you’ll know how the working converts the reciprocating motion of the engine into rotary motion of the crankshaft. you can read that at the end of this article.

Voltage sensor:

the functions of voltage sensors in automobile engines are to manage the idling speed of the vehicle. it ensures the speed is increased or decreased as required.

Manifold absolute pressure sensor (MAP sensor):

The MAP sensor types monitor the engine load by calculating the difference between manifold pressure of the car and the outside pressure to ensure the engine takes fuel base on the changes in pressure. The failure of this sensor also causes high fuel consumption.

Spark knock sensor:

The purpose of the spark knock sensor is to ensure fuel is burning smoothly and unexpected detonation occurs. Detonation is very dangerous to the engine as the piston rings will break, the head gasket will fail, and even damage the rod bearings. Fixing the problems can be quite expensive, which is why serious note should be taken on the information sent by the sensor.

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Fuel temperature sensor:

At a constant rate, there is a sensor that monitors the fuel temperate to ensure fuel consumption is optimum. A cold fuel will take longer to burn because of its higher density, while warn fuel tends to burn faster. The sensor makes sure the fuel is injected at the right temperature and speed so that the engine can work smoothly.

Oxygen sensor:

These types of sensors help to determine the amount of oxygen presented in the exhaust pipe. It determines if the vehicle is burning rich or lean based on the sensor calculation. The failing of the device will cause more fuel consumption, idle and even cause the car to jerk.

Various types of sensors and their functions in tabular form:

STT Sensor Main Function
1 The Mass Air Flow Sensor Calculates the density and the volume of the air taken in by the engine
2 The Engine Speed Sensor Monitors the spinning speed of the crankshaft
3 Oxygen Sensor Measures the amount of unburden oxygen presented in the exhaust pipe
4 Manifold Absolute Pressure Sensor Measures the manifold pressure inside and outside
5 Spark Knock Sensor Ensures that the fuel is burned correctly
6 Fuel Temperature Sensor Ensures the right amount of fuel is injected to keep the motion smoothly
7 Voltage Sensor Manages the car speed and ensures the speed is controllable

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Working Principle

The working of car sensors is quite simple, interesting and easy to understand. For a simple understanding of these sensors, let think about human sense organ which includes the nose, eye, mouth, hand, ear. All these human parts receive information from life phenomena and send it to the brain which then makes a decision. The same thing happens to automobile sensors, they sense what is happening to the vehicle and send the information to the computer which then makes thing right.

The working of sensors is accomplished by the process called multiplexing, it’s consolidated wires in a microprocessor that ensures the operation never go out of control. giving an example on sensor powering engine cooling system, since the cooling system is broad it could contain one or more sensor. So, immediately the engine starts running, the sensors that monitoring every aspect of the cooling system, starting from the radiator to the overflow tank. So, whenever any component of the cooling system goes wrong, information is sent to the driver. The sensor will notice low coolant in the system.

Early applications of sensors in an automobile are quite intense as it sends information to an analogue processor. The processor makes a decision based on simple algorithms to manage the condition of the system. The analogue system could only handle predefined values, so any value aside from ones programmed. If an unknown error occurs, the system will end up failing.

Watch the video to learn more on sensors working:

Advantages and disadvantages of car sensors


Below are the benefits of sensors in automobiles:

  • Sensors are made life easy for drivers.
  • Faulty components are easily detected
  • Automatic control is common with vehicles that feature sensors.
  • The engine is properly maintained with the devices.
  • Every adjustment is done precisely with sensors.
  • The driver receives warming information on bad components.

Read more: Understanding Cooling System in Internal Combustion Engines


Despite the advantages of the sensor, one big limitation still happens. Below are the disadvantages of sensors in automobiles:

  • Almost all modern cars use a variety of different sensors to collect the right information. The disadvantages of using many different sensors are that they can fail over time which may lead to costly replacements.

In conclusion, we have given the definition and functions of sensors in automobiles, which one of them is to monitor and send information about the engine components. we also saw the various types of sensor and their functions in tabular form. Working, advantages and disadvantages of sensors was also explained.

I hope you enjoyed the reading, if so, kindly comment, share and check some other interesting topics to gain more knowledge. Thanks!

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