ASE Mechanical and Electrical Components Certification (B5) Practice Test 2025 - Free ASE B5 Practice Questions and Study Guide

The term "parasitic draw" refers specifically to the current drain that occurs from electrical systems in a vehicle when it is turned off. This draw can originate from various components such as alarms, clocks, and other electronic devices that remain operational even when the vehicle isn’t running.

Understanding this concept is crucial for diagnosing battery drainage issues. If a vehicle's battery discharges quicker than expected, checking for parasitic draw becomes a key troubleshooting step. Typical acceptable limits for parasitic draw are usually around 20-50 milliamps, and if the draw exceeds this range, it could lead to significant battery drain over time.

This aspect is fundamental in vehicle maintenance and electrical troubleshooting, emphasizing the importance of ensuring that vehicle electrical systems are not unduly consuming power when the vehicle is not in use.