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Home >> Lexus >> 1997 >> LX 450 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Testing >> Fuel System >> Fuel Pump Control Circuit >> Circuit Opening Relay
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Circuit Opening Relay

Circuit opening relay controls the 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 to the other side of circuit opening relay. When proper input signals are delivered to the Engine Control Module (ECM), the circuit opening relay ground circuit is grounded at ECM terminal FC. Circuit opening relay then provides voltage to fuel pump relay for fuel pump operation.