Non-contact 6 - 24 V power tester that lets you efficiently and reliably check the power flow in cars and other devices. The tester works great for checking bulbs, batteries, cables, and fuses.

Ground the tester's clip, like to the car's chassis, and touch the tip to the spot you wanna test, just like with a test light. If there's voltage at that spot, a light on the tester will come on.