This automotive circuit fault probe tester is engineered for accurate and efficient electrical diagnostics across passenger vehicles, SUVs, and commercial trucks. Designed as a high-precision current tester, it measures up to 20 amperes on 48-volt automotive systems, detecting even the smallest fluctuations to help identify short circuits, fuse issues, relay faults, and parasitic draws. Built with a bright front-facing light, this circuit tester illuminates dark or tight engine compartments, allowing safe operation during nighttime maintenance or roadside inspections. The blue backlit LCD screen provides clear visibility in sunlight, low light, and harsh workshop conditions, ensuring test results remain easy to read at all times. Constructed from durable ABS/PC material with a non-slip rubber-coated grip, this fuse blade checker withstands demanding automotive environments while offering comfortable handling during extended diagnostic sessions. Its compact 1-piece design makes it easy to store in toolboxes, glove compartments, or mobile repair kits. Powered by a long-lasting 23A battery, the tool supports multiple tests without frequent replacement, making it ideal for mechanics, technicians, and automotive DIYers. Whether used as a car relay tester, current detector, or wire tracer electrical tool, it delivers fast, reliable performance for a wide range of circuit testing needs.