Circuit Opening Relay
Circuit opening relay controls fuel pump circuit. ECU receives input signal at STA terminal when engine is cranking. This same starter signal is also applied to terminal STA of circuit opening relay. Starter signal energizes circuit opening relay during cranking, which in turn, activates fuel pump. On Camry, Corolla (4A-GE), Cressida, Land Cruiser, Pickup, Previa, Supra (7M-GE) and 4Runner, circuit opening relay is grounded through airflow meter when it senses airflow to engine. On Celica, Corolla (4A-FE), MR2, Supra (7M-GTE) and Tercel, circuit opening relay is grounded by ECU through FC terminal.
NOTE:
Components are grouped into 2 categories. The first category covers INPUT DEVICES, which control or produce voltage signals monitored by the control unit. The second category covers OUTPUT SIGNALS, which are components controlled by the control unit.