Diagnostic relay tester for checking the general condition and functionality of the most common automotive relays.

The tester checks the proper operation of the relay contacts by connecting it to the car battery. It monitors the pin configuration, the closing and opening time of the contacts, and the operating sequence of the relay during each test session.

• Connect the power cables to the car battery: the black clip to the negative terminal and the red clip to the positive terminal.
• The tester is activated when the LED lights up RED.
• Check the relay before placing it in the tester. Select the "4-pin" socket if it is a 4-pin relay or the "5-pin" socket if it is a 5-pin relay.
• Insert the relay into one of the three contacts.
• Press the TEST button.

The tester checks the pin configuration of the relay being tested. It will indicate with a RED LED if the relay is faulty or if any pin is damaged. The tester will open and close the relay 10 times for testing. The time from contact closing to opening is monitored by the tester, and if the test time exceeds the specified limit, the relay is faulty. The tester will immediately light the RED LED.

The tester will check the relay sequence after testing the closing and opening times of the contacts ten times. The tester will light a GREEN LED if the test is successful.