An OBD scanner is an essential engine diagnostic tool designed to read, interpret, and clear trouble codes stored in a vehicle’s onboard computer system. Compatible with most vehicles manufactured after 1996, these scanners connect directly to the OBD-II port located under the dashboard and provide real-time monitoring of engine performance. They can track multiple parameters, including RPM, fuel system efficiency, coolant temperature, oxygen sensor data, and more, allowing both drivers and mechanics to identify underlying issues before they become major failures. OBD scanners are available in wired or wireless models, with many modern versions connecting to smartphones via Bluetooth or Wi-Fi for advanced reporting. Their primary function is to detect the source of the Check Engine Light (CEL), helping users troubleshoot and resolve problems efficiently. By providing quick and accurate insights, OBD scanners save both time and money on unnecessary repairs. In addition, they contribute to environmental protection by ensuring engines run efficiently, reducing emissions caused by faulty components. These devices are suitable for DIY car owners who want to maintain their vehicles and for professionals who require comprehensive diagnostics for repair services. Ultimately, an OBD scanner is a vital tool for ensuring vehicle health, improving performance, and supporting preventive maintenance.