Control Relay Control

Control relay consists of main relay that provides supply power to engine ECU and various actuators and fuel pump relay that drives fuel pump.
Main relay control will operate as soon as ignition switch turns on.
Turning ignition switch on, IG supply power will be, input through control relay terminal 8, and then the power supply will flow through magnetizer coil (L2) and then control relay terminal to engine ECU terminal B09.
As current flows through magnetizer coil (L2), main relay operates.
When main relay operates, IG supply power at control relay terminal 4 will go through main relay contact to control relay terminal 2 and terminal 3, and then the current will supply power to engine ECU and various actuators.
As to fuel pump relay control, when turning on ignition switch current will flow through control relay terminal 7, and then magnetizer coil (L1) to engine ECU terminal A20.Then ECU of the engine fuel pump relay control function will control fuel pump operation turning on/off engine ECU terminal A20, depending on engine rpm.Fuel pump relay will not operate at engine speed of 50rpm or less and operate only at engine speed of 50rpm or above when ignition switch is on.
Without the logic, fuel pump will continue to operate though car accident occurs with IG key on, and then may generate fire by fuel leak. Therefore the logic is newly added to prevent possible fire under car accident.

You can check the actuator actual value and status and activate it when it is possible by AutoHex Diagnostic Scanner under the supported car brand and according to engine type.

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