Red Seal Automotive Service Technician Practice Exam

What does a scan tool do in automotive diagnostics?

1. Measures tire tread depth

2. Analyzes engine performance data

3. Checks brake fluid levels

4. Inflates tires

The correct answer is: Analyzes engine performance data

A scan tool is an essential device used in automotive diagnostics that primarily focuses on analyzing engine performance data. It connects to the vehicle's onboard diagnostic system (OBD-II) to retrieve information about various systems and components, including error codes, sensor readings, and performance metrics. This information helps technicians diagnose issues with the engine and other critical systems, allowing for precise repairs and maintenance. Using a scan tool, a technician can monitor real-time data related to the engine's operation, such as air-fuel mixture, ignition timing, and exhaust emissions. Additionally, the scan tool can clear error codes once repairs are completed, ensuring that the vehicle's systems are functioning properly and that any faults have been resolved. In contrast, the other options involve tasks that do not align with the primary functions of a scan tool. Measuring tire tread depth relates to tire maintenance, checking brake fluid levels pertains to brake system upkeep, and inflating tires is a basic maintenance task unrelated to data analysis. Thus, the specific capability of a scan tool to analyze engine performance data makes this option the correct answer.