HomeCar RepairWhat Does an OBD2 Scanner Do?

What Does an OBD2 Scanner Do?




Before looking at what an OBD2 scan tool does, it is important that we define what an OBD scan tool is. An OBDII diagnostic scanner is a system that constantly monitors emissions and electrical sensors in your car while it is being driven. A good number of cars if not all made from 1996 or newer have a standardized computer system. An OBD system can diagnose a fault even before the driver detects it. Hence, it is very crucial that you have this tool or regularly take your car to a mechanic to be checked.

A warning or check engine light comes on when your vehicle is not functioning well. This allows the driver to know that his/her car has a problem. From there, the driver has to check the error codes using a code reader or car diagnostic scan tool. So, it is vital to know what a diagnostic scan tool does for you so that you can get to read, and clear codes, retrieve data, carry out tests, and many other functions.

Types of OBD2 scanners

Code readers

OBD2 code readers are normally used to read and erase error codes in OBDII compatible vehicles built from 1996 or newer. They are cheap and very easy to use. Code readers have a few inherent limitations in that they usually don’t have any data on manufacturer specific codes and provide limited or no access to other forms of data.

Scan tools

OBDII diagnostic scan tools come with a wide array of features and are more costly when compared to code readers. These provide additional info or access to manufacturer specific codes, record and offer live data, and also give troubleshooting info. They are more sophisticated and a bit challenging to use.

What does the OBD2 scan tool do?

As seen above, the work of the OBDII scanner depends on whether it is a basic code reader or a more advanced scan tool. If it is a basic code reader, it will only read and clear codes, while if it is an advanced scan tool, it will not only read and clear codes but as well view recorded and live data, and perform different tests.

Each and every OBD2 scan tool provides some basic function, which is to read and clear codes. Also, these diagnostic scan tools can also provide the ability to check pending codes that haven’t activated the check engine light, and offer access to a lot of info. Information from almost every sensor that gives an input to the onboard computer can be seen through an OBD2 scanner and some scan tools can as well set up custom lists of parameter IDs. In addition, there are diagnostic scan tools that give access to readiness monitors and other data.

How OBD2 scanners function?

OBD2 scan tools are very easy to use since they are all standardized. The scan tools utilize the same connector, which is defined as SAE J1962. Basic diagnostic scanners function by simply placing a universal plug into the OBD2 diagnostic connector in a car. Other advanced scanners as well include modules or keys that augment the universal connector in order to access or interact with OEM-specific data.


Now that you know how an OBD2 code reader functions, you can go ahead and acquire a quality obdii diagnostic scanner and read and clear fault codes.


Please enter your comment!
Please enter your name here

Recent posts