Posted on 4/1/2025
The check engine light (CEL) is a crucial indicator that your vehicle's onboard diagnostics system has detected a problem with one of its components. To properly diagnose and address the issue, mechanics and technicians use a variety of tools and follow specific processes. Here’s an overview of the tools and steps involved in diagnosing a check engine light: OBD-II Scanner (On-Board Diagnostics II): The first and most essential tool for diagnosing the check engine light is an OBD-II scanner. This device connects to the vehicle's OBD-II port (usually located under the dashboard near the driver's seat) and retrieves diagnostic trouble codes (DTCs) stored in the vehicle's computer system. These codes are alphanumeric, providing clues to the malfunctioning system or component. The scanner can also display real-time data such as engine performance, fuel efficiency, and sensor readings. Code Interpretation: Once the OBD-II scanner pulls the DTCs, the mechanic interpre ... read more