The circuit opening relay (COR) has the task of transmitting power to the fuel pump when the engine is running or has been started.
Circuit opening relay operationThe circuit opening relay is a safety feature that allows the fuel pump to only have power when the engine is running. The only way the COR would disconnect power to the fuel pump would be an incident where the engine has stopped or the fuel line burst. In that case, the COR will be in charge of turning the fuel pump off and it will prevent any leakage from the fuel line.
Common issues with a faulty circuit opening relayA faulty circuit opening relay can cause the feature to function improperly, like when the engine has stalled or the fuel line has burst.