Universal Compatibility: This relay tester is compatible with various vehicle types, offering a versatile solution for testing relays in automotive electrical systems. Accurate Diagnosis: Designed to test relays, this tool helps identify potential issues within a vehicle's electrical setup. Easy to Use: Featuring a straightforward design, this tester is user-friendly and suitable for individuals with limited automotive repair experience. Color: Red + Black Material: Plastic Instructions: 1. Connect the power leads to the car battery black alligator clip to the negative terminal, red alligator clip to the positive terminal. 2. The tester is powered when the LED illuminates red. 3. Examine the relay before inserting it into the tester. For a 4-pin relay, select "4 pin" on the tester; for a 5-pin relay, select "5 pin." 4. Insert the relay into one of the three receptacles. 5. Press the "TEST" button. 6. The tester will analyze the pin configuration of the relay. The red LED will illuminate if the relay does not match common automotive relay configurations or if the relay pins are damaged. 7. If the pin configuration is correct, the tester will cycle the relay open and closed 10 times to evaluate contact closure and opening timing. The red LED will illuminate immediately if the timing exceeds acceptable limits. 8. After completing the 10 cycles, the tester checks relay consistency. A green LED indicates a passed test; a red LED indicates failure. 9. Disconnect the power leads from the battery and remove the relay from the tester. Attention: 1. The vehicle battery must be 12V, with voltage between 11V and 15V. 2. Best suited for relays with coil resistance above 20 ohms. Package Contents: 1 x Car Relay Tester Note: Other items not included. Note: Lighting conditions and display settings may cause slight variations in the color appearance between the product image and the actual item. Measurement may vary by 13 cm.