First, clip the tester's clip onto the car battery, the black clip onto the negative pole, and the red clip onto the positive pole. When the red LED is on, it means that the tester starts the test. Check the relay before the test. Select the appropriate socket according to the pin, insert the relay into the socket, press the "Test" button, and the tester will automatically detect the pin position of the unknown relay. The tester will automatically detect the pin position, release time and the consistency of the relay at each test stage. If the tester lights up the green LED indicator, the relay is normal; If the red LED is on, the relay is abnormal. Compatible with most General Motors relays on the market. The 11V-15V battery of the vehicle needs to be connected during the test. The car battery must be 12V, and the battery voltage must be between 11V and 15V; 2. The applicable resistance should be more than 20 . Our automobile relay tester is small, portable, suitable for mobile work or easy to store. Its compact design makes it easy to use wherever you are. The relay tester will provide you with the required results quickly and easily. Color: as shown in the figurePackage includes: 1 * testerNote: 1. Please allow a little error due to manual measurement. Please make sure you don't mind before bidding< br> 2. The color may vary depending on the display. Please understand< br> Note: Hello, please pay attention to your shipping address when purchasing products. If your receiving information (such as name, street, house number, doorbell/email without name) is incorrect, the order will not be delivered correctly.)