Wiring Diagram For Automotive Relay. 4 pin normally open relay with the switch on the positive side of the control circuit. You can think of this as the switch in off.
87 and 87a are the two contacts to which 30 will connect. When the relay is energized on pins 3 and 5 have continuity. They are also used when a device draws heavy amperage such as car alarms remote starts fog.
2 pack 12v 3040 amp 5 pin spdt automotive relay harness socket set.
Looking at the diagram we see the pinout of a typical 12v relay. The following simplified circuit diagram is often used to easily understand how a relay operates. Each of the connections has a number. Iso relays are currently used by almost all automotive manufacturers today.