Circuit Opening Relay

Circuit opening relay controls fuel pump circuit. When engine is cranking, circuit opening relay receives a start signal.

Start signal energizes circuit opening relay during cranking. Circuit opening relay then provides voltage to fuel pump or fuel pump relay. Fuel pump relay is used on Land Cruiser, MR2 Turbo and Previa Supercharged only.

On Land Cruiser, Pickup, Previa Non-Supercharged, T100 3.0L and 4Runner fuel pump switch in airflow meter provides ground for circuit opening relay. On all other models, circuit opening relay is grounded by ECM through the FC terminal.