SYSTEM / Electrical System OUTLINE The electrical circuit is broadly divided into the main circuit, monitor circuit and control circuit. Main Circuit The engine and accessory operation related circuit. Monitor Circuit The electrical circuit group consists of the monitors, sensors and switches, and displays the machine operation status. Control Circuit (Refer to Control System / SYS- TEM.) The control circuit is categorized into the engine, pump and valve control circuits. Each circuit con- sists of the actuators such as solenoid valves, MC (main controller), ECM (engine control module), switch boxes, sensors and pressure switches. T2-5-1