What Is OBD?

OBD stands for On-Board Diagnostics, as the name implies, it’s a computer system inside of a vehicle that tracks system failure. This on-board computer system collects information from the network of sensors inside the vehicle, then provide general feedback on vehicle performance. If any auto part went wrong, it would alert the user to problems at its earliest. A technician can then simply locate the problem and diagnose the problem by checking OBD system. Both drivers and technicians benefit a lot from OBD systems, it becomes much easier for them to better understand vehicle diagnostics. What’s more, with the development of OBD system, now we can monitor the volume of the emission generated by vehicles and determine whether they pollute the environment or not.  

You must be curious about how does it work? Let’s start from knowing its components: ECU (Engine Control Unit), sensors covering every area of the vehicle, DLC (Diagnostic Link Connector). Here comes the working process of OBD system: Firstly, as you know, sensors are connected to various vehicle components. Once any failure of auto part detected, error code with specific source would be sent to vehicle ECU. Secondly, DLC is used to interface an OBD compliant scan tool with the PCM allowing access to on-board diagnostics and live data streams. Finally, if the input data from sensors beyond the normal range, ECU would save the information as Diagnostic Trouble Code and send a signal to the display and indicate a problem.

Since the initial development of OBD, vehicle monitoring systems have undergone several iterations. Today, OBD serves as a standardized system that dictates the connectors and trouble codes used, making it easy for technicians to service a wide range of vehicles quickly and accurately.