Complete Guide to OBD2 Scanners: What Every Car Owner Should Know

What Is an OBD2 Scanner?

OBD2 (On-Board Diagnostics, Generation 2) is a standardized system built into every car sold in the US after 1996 and most vehicles worldwide after 2001. It gives you a direct window into your vehicle's electronic control unit (ECU).

An OBD2 scanner plugs into the 16-pin DLC (Data Link Connector) port, typically located under the dashboard on the driver's side, and reads the data your car's computer is constantly logging.

How Fault Codes Work

When your check engine light comes on, the ECU stores a Diagnostic Trouble Code (DTC). These follow a standardized format:

• P — Powertrain (engine, transmission)