Car Sensors

Sensors are an electrical device that monitors an item on the vehicle and reports its state back to the computer. The computer takes data from this and other sensors and can then make a decision based on what the sensors are telling it. Let us take the throttle position sensor for example. When you put your foot down harder on the accelerator pedal it detects this and tells the computer we need to accelerate.The computer then monitors a host of car engine sensors to make sure the engine is responding correctly to the amount of input from the driver's right foot.

Some of the functions it does is enriches the air fuel mixture by adding fuel, monitors oil pressure and monitors O2 levels in the exhaust gases. All this makes today's engines very efficient in their operation.At the other end of the scale you get the parking sensor. This sets off the beeper in the dash when you are getting to close to an object.

Currently most modern vehicles have approximately 30 sensors. The all do different jobs. Some are to keep the vehicle running efficiently like Crankshaft and Camshaft position sensors in the engine. Some are for safety, like blind spot detection in the mirror or the ABS sensor that keeps the wheels turning when the brakes are jammed on. Some are for driver/passenger comfort, like cruise control and cabin temperature.

Cruise control is a good example of a number of different sensors getting together to perform a function. There is no such thing as a cruise control sensor. There can be a cruise control module which is the part of the computer that looks after the cruise control. Others monitor states so a driver can make decisions. Some classics like the fuel gauge and speedometer are proven to cause issues if ignored and more recently the tyre pressure monitor.

They can be quite large like a mass airflow sensor or a throttle position sensor, though most are small and screw into or on the part they are monitoring. They all have an electrical connector so they can be easily unplugged if they need to be replaced. Some have wiring from the sensor to the connector. Most vehicles will need a sensor replaced at some point in their lifetime.