Universal Compatibility: This relay tester is compatible with all types of cars, making it a versatile tool for any car owner. Accurate Diagnosis: With its ability to test relays, this tool can help diagnose any issues with your car's electrical system. Easy to Use: The simple design of this tool makes it easy to use, even for those who are not experienced in car repairs. For Relay Tester can quickly detect whether your relay is working properly. It is easy to use and suitable for automotive relays on the market. It supports 12V relay testing During testing, the equipment needs to be connected to a 12V car battery. When testing, turn the switch to 4PIN or 5PIN according to the relay's pin position. the test button and the tester light up the green LED and flash, indicating that the relay is working. If the test button is pressed and the red LED is on, it indicates that the relay is not working. Operating instructions: During the test, clamp the red clip onto the positive pole of the battery, while the black clip onto the negative pole of the battery When testing a 12V relay, it needs to be connected to a 12V battery, After connecting to the power supply, the device turns on a red light, which allows for the insertion of a relay Test the 4-pin relay to set the switch to 4PIN, and test the 5-pin relay to set the switch to 5PIN After connecting the relay and adjusting the foot switch, you can the button During the 6 test, if the foot position is incorrect or the relay is damaged, the red LED light up during the test. When the foot position is set correctly, the tester light up the green LED and flash the green light 10 times to indicate that the relay is working. Colour:Black & Red Material:ABS Package Contents: 1 * Car Relay Tester 1 * Englishinstruction manual Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.