EFI Main Relay (ECHO)

EFI main relay may also be referred to as EFI relay. EFI fuse supplies constant battery voltage to one side of EFI main relay. When ignition is turned on, voltage is supplied to other side of EFI main relay. EFI main relay is then energized and provides battery voltage to circuit opening relay, +B terminal of Engine Control Module (ECM) and various other electrical components. For EFI main relay location, see EFI MAIN RELAY LOCATION  table.