It is a quick go/no-go tester relays that provides with indication of the general health and functioning of the most common Automotive relays. Tester will check for proper functioning of the relay contacts by connecting the car battery (11V--15V) to the relay coil. Tester will watch the pin configuration, the time to contacts closure and opening, consistency of the relay during each test session, Tester will light the GREEN LED if all passed during the test session, if not light the RED LED. Using method: 1. Connect the power leads to the car battery --black alligator clip to negative terminal, red alligator clip to positive terminal. 2. Tester is powered up when the LED illuminates in RED. 3. Check the relay before plugging into the tester. If it’s a 4 pin relay, select 4 pin on the tester. If it’s a 5 pin relay, select 5 pin on the tester. 4. Plug in the relay into one of the three receptacles. 5. Press the TEST button. 6. Tester will check the pin configuration of the unknown relay. Tester will light the RED LED if the unknown relay is not the same to the most of common automotive relays or the pin of the unknown relay is destroyed. 7. Tester will open and close the relay 10 times for testing the time to contacts closure and opening if the pin configuration of the relay is right. Tester will light the RED LED immediately if the time is overtime. 8. Tester will check the consistency of the relay after testing the time to contacts closure and opening ten times. Tester will light the GREEN LED if the test passed, if not light the RED LED. 9. Disconnect power leads from the car battery and remove relay from the tester. Specification: Color: As Shown. Material: Plastic, Metal. Note: The car battery must be 12V battery, and the voltage of the battery is among 11V-15V. Ideal for coil resistance above 20 ohms. There might be a bit color distortions due to different computer resolutions. There might be a slight errors due to different hand measurement. Package Includes: 1 x Car Relay Tester