Lexus 85940-48010 Relay Assy, Windshield Wiper

To test a relay, connect an ohmmeter across the two terminals of the power circuit; continuity should not be indicated. For a typical four-terminal normally open relay, connect an ohmmeter to the power circuit terminals; the meter should indicate continuity when the relay is energized and no continuity when not energized. Then, connect a fused jumper wire between one control circuit terminal and the positive battery terminal, and another jumper wire between the other control circuit terminal and ground. The relay should click and continuity should be indicated on the meter. If it doesn't click, try swapping the jumper wires.

Some relays may be marked to help identify which terminals make up the control circuit and which make up the power circuit. If not marked, refer to the wiring diagrams to determine the proper hook-ups.