Car Repair and Maintenance

Types of Car Sensors and Their Functions

Types of Car Sensors and Their Functions

This post explains the types of car sensors and their functions.

What is a car sensor?

The automobile sensor is an electronic instrument that is designed to help monitor several functionalities of the automobile. The vehicle’s sensor is designed to send all information it receives from its monitoring to the Electronic Control Unit (ECU) or driver.

According to Mercedes, your vehicle sensors are important when it comes to processing a range of values and determining what levels are accurate for each individual part of the vehicle.

The ECU, on some occasions, automatically adjusts the vehicle component based on the information received from the sensor. In today’s article, we will discuss the various types of sensors on your car and their functions. 

Sensors are designed to function in the below-listed ways;

  • Monitor several functionalities of the vehicle parts, including; its temperature, emission levels, oil pressure, cooling system, engine, speed, etc.
  • Sensors functions in the different part of the body, such as the eyes, nose, mouth, tongue, and hands. The sensors of the body give a proper understanding of sensor functioning. They send signals to the brain to make a decision. 
  • Car sensors function like the body parts in sending information to the ECU. The ECU then makes appropriate adjustments and sends a proper signal to the driver.
  • The sensors start operations once the car’s engine is turned on. 
  • All parts of all new vehicle models have sensors that include the least essential vehicle parts.

types of car sensors

Types and Functions of Various Car Sensors

Several sensors perform different functions across the vehicle parts. The basic function of the sensors does not change. The task of the sensors involves tracing and monitoring all aspects of the vehicle. The information gathered is then sent to the ECU for processing, and when the ECU can’t make appropriate changes, it sends a warning to the driver. This warning is usually displayed on the dashboard. 

Types of car sensors

The table below provides a listing of several car sensors and their functions.


        Sensor    Function
Air-flow sensorIt monitors the density of air entering the vehicle’s combustion chamber.
Engine knock sensorThis sensor monitors the air-fuel mixture and ensures it is ignited properly. Also, it monitors the engine knocking.
Engine speed sensorThe Engine speed sensor is designed to monitor the speed of the engine’s crankshaft.
Camshaft position sensorIt monitors the position and proper timing of the camshaft. This sensor monitors the camshaft positioning and its timing.
Manifold Absolute Pressure (MAP) sensorThis sensor is designed to monitor the engine load. It achieves this by measuring the pressure difference between the manifold and its external.
Throttle position sensorThis sensor works to monitor the throttle valve position.
Voltage sensorThis sensor gathers information on the idling speed of the vehicle.
Oxygen sensorThis sensor gathers information on the level of oxygen present in the exhaust gases.
NOx sensorThis sensor is designed to measure the number of Nitrogen Oxides (NOx) in exhaust gases.
Temperature sensorThis sensor is designed to measure the engine’s temperature.
Fuel temperature sensorThis sensor is designed to gather information on the temperature of the fuel as it enters the engine.
Speed sensorThis sensor is designed to measure the speed of the vehicle wheels.
Parking sensorThis sensor is designed to look for obstacles on the front or rear parts of the vehicle and notify the driver.
Rain sensorThis sensor monitors for rain and provides the ECU with signals for wiper activation.

Let us now go into details on each of the sensors listed in the above table.

1. Air-flow sensor

  • This sensor is usually placed on the inside of the combustion chamber.
  • Failure of this sensor can cause increased fuel consumption and stalling engine.
  • It measures the density and volume of air that enters the vehicle’s engine.

2. Engine knock sensor

  • When this sensor goes bad, the engine efficiency reduces, damaging its components.
  • The sensor signals a fault in the ignition’s air-fuel mix.
  • It monitors the air-fuel mix in the vehicle’s ignition.
  • Knocking results from air and fuel, causing the spark plug to spark, thus starting the vehicle.

3. Engine speed sensor

  • This sensor provides the ECU with information on the position and speed of the crankshaft.
  • The ECU calculates the time needed for the fuel injection to activate ignition sparks with the information provided.
  • This sensor is placed on the crankshaft.
  • When this sensor is bad, it reduces the engine’s efficiency.
  • It is a very important car sensor.

4. Camshaft position sensor

  • A vehicle’s camshaft controls the exhaust and inlet engine valves.
  • The sensor monitors the air entering the camshaft and the burnt gases escaping from the cylinder simultaneously.
  • Damage to the cylinder may occur, or power output may be affected when this sensor is damaged.

5. Manifold Absolute Pressure (MAP) Sensor

  • This sensor is designed to provide information on the engine load.
  • A faulty MAP results in increased fuel consumption.

6. Throttle position sensor

  • It monitors the throttle valve position when you step on the accelerator pedal.
  • When this sensor is bad, there is reduced power delivery.

7. Voltage sensor

  • The sensor monitors the vehicle’s idling speed.
  • The sensor also ensures the ECU has accurate information to reduce or increase the vehicle’s idling speed.

8. Oxygen sensor

9. NOx sensor

  • This sensor helps to monitor the NOx content of exhaust gases.
  • It is an essential sensor as vehicles have harmful gas emission stipulations.

10. Temperature sensor

  • It helps to monitor the engine’s temperature.
  • It helps in the proper functioning of the vehicle’s cooling system.
  • Notifies the driver of the radiator’s functionality

11. Fuel temperature sensor

  • It monitors fuel temperature to ensure optimum consumption.
  • Cold fuel has high density and burns slowly, and the converse is also true.

12. Speed sensor

  • Monitors the speed of each wheel when driving
  • It is a crucial sensor for vehicles as it helps to prevent skidding off the road.

13. Parking sensor

  • This sensor alerts the driver to any obstacle in the car’s path.
  • It helps to engage the automatic braking system.
  • Helps in safe parking of vehicles.

14. Rain sensor

  • It is located on the windscreen.
  • It helps in activating the vehicle’s wipers.


Here you have a list of common vehicle sensors and their functions. I hope this article has provided you with tangible information on your car sensors. 

You will also, with this article, know which of the sensors are at fault the next time you notice a notification on your dashboard. Till next time, have a great day.

Latest posts by Bernard Juchli (see all)

Bernard Juchli

Bernard Juchli is an experienced racer, mechanic and team owner who trusts Avon Tyres.Bernard is the lead driver and force behind his Big Dog Garage Race Team. He is the General Manager and Chief Mechanic of Jay Leno’s Garage. Bernard and his crew of seven are responsible for all repairs, restoration and fabrication of Jay’s incredible automobile and motorcycle collection.

Related Articles

Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button