Most cars today have a lot of sensors, which use to provide the driver and passengers with important information about the current car’s operating status. A sensor is a measuring device that converts physical properties into electrical signals and provides that information as feedback.
The location of the sensors depends on their function. They can be positioned at different places on the car and be part of more than one system. In this article, let’s find out how many sensors on a car today.
How many sensors do cars have?
At the minimum, a typical car has 30 sensors on average that can be classified according to their major areas of car systems applications – powertrain, chassis, and body. Whereas modern and luxury cars have car sensors that range from 100 up to 200. The number of automotive sensors depends on the car, manufacturer.
Furthermore, here is a list of car sensor classifications:
- Rotational motion sensors
- Pressure sensors
- Position sensors
- Temperature sensors
- Mass airflow sensors
- Exhaust gas oxygen sensors
- Engine knock sensors
- Linear acceleration sensors
- Angular-rate sensors
- Occupant Comfort/convenience sensors
- Near-distance obstacle detection sensors
- Far-distance obstacle detection sensors
- Other emerging state of the art sensor technologies
Alongside the Electrical Control Unit (ECU), these sensors made it possible to diagnose automotive problems easier. Did you know that the earliest sensors have been around since the 1950s?
These sensors would simply turn on a light to alert whenever there is a problem. While it was around 1978 when General Motors introduced the ECU which shaped the evolution of cars in every aspect of innovation.
Today, we are in the era of self-driving cars that can perceive their surroundings with the help of a combination of sensors such as camera, radar, ultrasonic and LiDAR sensors.
|Car Sensor||Main Function||Location|
|Engine speed Sensor||Measure gear or target wheel speed and position||Side of a wheel axle or of a traction motor axle.|
|Camshaft position sensor||Determine the exact position and speed of the camshaft drive||The cylinder head of the engine|
|Crankshaft position sensor||Measures the rotation speed (RPM) and the precise position of your engine’s crankshaft||Behind the harmonic balancer|
|Oxygen sensors||Measure the amount of oxygen in the exhaust gases||Near the catalytic converter|
|Oil pressure sensor||Alerts the driver when the oil pressure is below the optimal level||Near the back and top of the engine compartment|
|Tire pressure monitor system||Monitors the air pressure in each tire||Inside the tire attached to the inner part of the r|
|Engine coolant temperature sensor||Measures the temperature of engine coolant||On top of the engine, next to the radiator|
Now that we have briefly answered how many sensors on a car today, let’s discuss some of the most important sensors found in modern cars in more detail.
1. Engine Speed Sensor
First, let’s take a look at speed sensors. The engine speed sensor is also known as the transmission speed sensor. Speed sensors are usually mounted on the side of a wheel axle or of a traction motor axle.
Its main function is to measure gear or target wheel speed and position. This information can be used to set engine functions and perform diagnostic tests.
Speed sensors are usually either inductive or optical sensors. An inductive or magnetic sensor is simply a mechanical device to measure how fast your vehicle is traveling. Whereas the other uses optical technology that can tell whether or not your car has hit something (from any angle) and will automatically stop it from moving if need be.
When that happens, it sends out an alert to the driver or passengers letting them know about this incident so they can take necessary action. Driving with a bad speed sensor can lead to some safety risks. Moreover, some of the car’s components may start to malfunction.
Another example would be ABS brakes which use sensors to detect when there is wheel lockup caused by panic braking or other forms of driver panic reaction while driving at high speeds on highways.
2. Camshaft Position Sensor
The camshaft position sensor is a small cylinder with wires coming from it and is usually located in the cylinder head of the engine and has a cylindrical portion that inserts into the head. You’ll have to refer to your owner’s manual for details about where it’s located on your particular car model.
The camshaft position sensor enables the engine control to determine the exact position and speed of the camshaft drive. It tells your engine computer how far each valve has opened so that it can be timed correctly when opening and closing them during operation.
If there’s any problem with this system, it’ll result in hard starting, poor performance, and other symptoms like rough idle or stalling out while driving.
You may also see warning lights on your dash or hear noises from under the hood when something isn’t working properly here. If either of these things happen regularly then I’d recommend having this checked out by an expert as soon as possible before any serious damage occurs.
3. Crankshaft Position Sensor
A crankshaft position sensor is a device that measures the rotation speed (RPM) and the precise position of your engine’s crankshaft.
It is usually mounted near the bottom of the block toward the front of the engine. In most car models, it can be found behind the harmonic balancer.
If the sensor fails, it cannot provide the right information on piston positioning in the engine and may cause the engine to misfire.
Other signs of a failing crank sensor include:
- The car won’t start
- Engine vibration
- Poor fuel economy
- Uneven acceleration
- Check engine light
It also measures engine speed by feeding this data to the computer, which then uses it for many different purposes including calculating how much fuel should be injected into your engine at any given time based on what RPMs you are driving at.
4. Oxygen Sensors
The oxygen sensor is located near the catalytic converter. Its function is to measure the amount of oxygen in the exhaust gases.
The O2 sensor reads the exhaust in real-time to determine the air-fuel ratio. It then sends the data to the computer, and the computer adjusts the mixture accordingly by controlling the fuel injectors.
Your car’s O2 sensor must be tested regularly at a mechanic, as this will help prevent problems such as engine misfires and gas mileage issues later on down the road.
There are two types of O2 sensors, the upstream and the downstream O2 sensor. The upstream O2 sensor is installed before the catalytic converter whereas the downstream O2 sensor is located after the catalytic converter.
Although a car with a broken oxygen sensor is driveable, it will cause higher fuel consumption and inefficient engine performance. If you notice any of these symptoms when driving around town, it could mean that there’s something wrong with your O2 sensor:
- Illuminated Check Engine Light
- Poor Fuel Economy
- Rough Idling and Engine Misfires
- Failing Emissions Test
- Black Smoke Emission
- Rotten Egg Smell
5. Oil Pressure Sensor
As its name would suggest the oil pressure sensor measures the oil pressure in the engine’s system. It was a collective term for two distinct sensors – the oil pressure switch and the oil pressure sender.
The oil pressure sender detects the oil pressure and sends it to the engine controller. Whereas the oil pressure switch will turn on a warning light in your dashboard once the oil pressure in your vehicle has fallen below the optimal level.
It’s usually mounted near the back and top of the engine compartment and is connected to the engine block. Since the oil pump circulates a constant supply of oil through this system, any damage to the oil pressure sensor will cause problems with your vehicle. The common symptoms include:
- Check engine light
- Oil pressure warning lights
- Rattling noise from the engine
- Inaccurate reading on the oil pressure gauge
- Throttle Position Sensor
A throttle position sensor (TPS) measures the open the throttle valve is and therefore controls the amount of air that can flow into the engine’s intake manifold.
The ECU uses this information to calculate how much fuel should be injected into each cylinder and when. This ensures that the correct mixture of air and fuel is delivered to the vehicle’s engine.
Throttle position sensors are located on the butterfly spindle/shaft so that it can directly monitor the position of the throttle. On older cars with carburetors, they were sometimes located in the distributor housing or attached directly to the camshaft by a mechanical linkage.
The TPS plays a crucial role in how much fuel the engine gets at any given time. Consequently, if your car’s TPS malfunctions, it can cause problems with acceleration, idle speed, and fuel economy.
6. TPMS sensor- Tire Pressure Monitor System
As you know, tires are very important to your vehicle because they help it to travel smoothly and safely. The TPMS sensor is a small device that monitors the air pressure in each tire and communicates this information with your car’s computer system.
It is usually found inside the tire attached to the inner part of the rim. Once the tires were removed from the rim, you’ll see a small cylinder, which is the tire pressure sensor. There are four TPMS sensors installed in a car: one per wheel (front and rear).
When the internal mechanisms sense that the tire pressure is 25% below the recommended pressure, it alerts the driver. For example, if your car’s tires should be filled with 34 psi, the dash light will come on when one of your tires reaches 26 psi.
7. ECT – Engine Coolant Temperature Sensor
ECT is a sensor that measures the temperature of engine coolant. The sensor acts as the thermometer of your engine, helping to maintain your car’s temperature. Depending on the CTS readings, the control unit adapts the injection time and firing angle to the operating conditions.
It is mounted on top of the engine, next to the radiator, and behind a plastic cover. If it fails, your engine will not be able to operate at its full capacity because you will have low-coolant levels. This can lead to overheating and eventual damage to your car’s internal parts.
We have written a comprehensive article looking at the symptoms of bad ECT here.
8. Self-driving Car Sensors
Cars have been getting smarter for decades. They now feature all sorts of computers, sensors, and software that help drivers avoid accidents and make driving safer. The year 2022, will bring more new sensors and assists to cars.
Self-driving cars like Tesla, take this technology a step further. They use cameras and sensors to detect objects in the vehicle’s path around corners or hidden from view. The car can then decide what actions to take — such as slowing down or changing lanes — based on the information it gathers about its surroundings.
Autonomous cars use a combination of sensors. Radar sensors monitor the position of nearby vehicles. Video cameras detect traffic lights, read road signs, track other vehicles, and look for pedestrians. Lidar (light detection and ranging) sensors bounce pulses of light off the car’s surroundings to measure distances, detect road edges, and identify lane markings.
The sensors combine this information with other data like street maps or GPS information to determine what actions should be taken by the car’s computer system — whether making a turn or stopping at a stop sign or red light.
This article answers the question: How many sensors on a car. We provided a list of car sensors that are crucial to optimal vehicle operations. You will now be able to find the exact position of your car sensors on different car models.
This is important as you can check for wear and tear, as well as malfunction when you are doing other car maintenance. You can also check for problems if your sensor does not work properly during this time.
Sensors are used in cars to alert drivers about various issues within their vehicles. The different types of sensors include those that detect things such as temperature changes, oil pressure, and tire pressure levels.