True or False: It is important to maintain good battery voltage when performing diagnostic scans to prevent modules from shutting down.

• A. True
• B. False
• C. Not important
• D. Not sure

Answer: (A)

A stable power supply is essential for reliable diagnostics. When you run a diagnostic scan, the vehicle’s electronic control modules and the scan tool rely on a steady voltage to stay awake, communicate correctly, and record data without interruption. If the battery voltage is low or fluctuates, modules may reset or enter a sleep/protection mode, communications can drop, and data can become corrupted or incomplete. That can look like a module shutting down mid-scan or producing false results. By keeping the battery healthy and the voltage within a normal range (roughly around 12.6 V with the engine off, higher when charging or running), you prevent these interruptions and ensure the scan proceeds smoothly. If the battery isn’t up to it, use a charger or external power source during the diagnostic session. This is why maintaining good battery voltage is important for diagnostic scans.