Before diving into testing, it's important to understand what a car relay is and how it functions. A car relay is an electrically operated switch that uses a low-power electrical current to control a higher power circuit. It acts as a bridge between circuits, allowing a small current to trigger a larger current, often controlling components like lights, motors, or air conditioning. A typical relay has four or five pins, which include the coil terminals and contact terminals (either normally open or normally closed).

    Tools Needed

    To test a car relay, you will need the following tools：