Circuit Opening Relay (ES300 & RX300)

Circuit opening relay controls fuel pump circuit. When EFI main relay is energized, EFI main relay provides battery voltage to one side of circuit opening relay. When ignition is turned on, voltage is supplied through IGN fuse to other side of circuit opening relay. When proper input signals are delivered to Engine Control Module (ECM), circuit opening relay ground circuit is grounded at ECM terminal FC. Circuit opening relay then provides voltage to fuel pump for fuel pump operation. On ES300, circuit opening relay is located in fuse/relay box at driver's side front corner of engine compartment, just in front of strut tower. On RX300, circuit opening relay may be located in fuse/relay box at driver's side front corner of engine compartment, near battery, or in relay box behind driver's side of instrument panel, just above the kick panel.