Tests both 12V and 24V relays!; 3 diagnostic trouble codes help define the cause of the bad relay!; Quick off-the-car relay tester.; Checks relay coil & switch contacts; Fails bad relays - Good/Bad indication, green light for PASS, red light for FAIL with flashing trouble code; Available as stand alone tester #192 and in kit form #193 with adapters for expanded testing; Relay Buddy 12/24 is a quick go / no-go tester for the most common automotive relays. This new version Relay Buddy tests both 12 and 24 volt relays. If the relay fails the test, 3 different trouble codes will advise you of the possible causes for the failed relay. The red LED will flash once, twice or three times to indicate the problem. Trouble code definitions are printed on the back of the tester for your convenience.; Relay Buddy 12/24 provides you with an indication of the general health and functioning of the relay switch contacts and coil. It will check the control side of the relay by applying a signal to the relay coil while it checks for proper functioning of the relay contacts. Relay Buddy operates the relay several times during each test session as it watches for consistency in every cycle. Relay Buddy will fail the relay and light the RED LED if any one of the cycles proves unsuccessful during the test session; Specifications: Tests 12 and 24 volt relays; Settable to 4 and 5 pin relay; Uses vehicle battery for power; 3 Diagnostic Trouble Codes - Green Light if relay is good - Red Light if relay is bad; Switch contacts are loaded to detect excessive resistance