Posted on 8/29/2025
When your check engine light suddenly appears on the dashboard, it’s easy to feel overwhelmed. The light can signal anything from a loose gas cap to a serious engine malfunction. That’s where diagnostic scans come in. But how accurate are they? Can a diagnostic tool actually tell you exactly what’s wrong with your vehicle? Let’s explore how modern automotive diagnostics work, what they can tell you, and why professional interpretation is key. What Is a Diagnostic Scan A diagnostic scan is performed using a tool called an OBD-II (On-Board Diagnostics) scanner. This device connects to a port in your vehicle and reads stored trouble codes that the car’s onboard computer generates when it detects something abnormal. These codes are usually labeled with a letter and a series of numbers (like P0301), which correspond to specific systems or types of malfunctions. Once a code is retrieved, a technician uses it as a starting point for further i ... read more