Switch Relay Wiring - SWH001. Spotlight wiring harness complete with relay and mouse style switch - Plus TOYOTA dash switch (suits selected models - see drawings). Features: Easy to install with supplied plugs and wires ready to plug together.. The square relay pinout shows how the relay socket is configured for wiring. This pinout image is only a 2-pole diagram for room on the page purposes, but you can get the picture here with this one since a 3-pole will just have 1 more set of contacts..