PURPOSE: To enhance the efficiency of a device by receiving data from a sensor, executing a control function by an electronic controller, and also controlling a display for showing the level of a sensed parameter thereby.

CONSTITUTION: Sensor data showing a plurality of parameter values is received by a device 10 through a wire harness 18. The device 10 processes the signals, in addition to their scaling, to form measuring instrument signals, and transmits them to an electronic controller 20 through a communication link 22. The electronic controller 20 executes various control functions by use of the measuring instrument signals, and also generates control signals followed by transmission to the device 10 through the communication link 22. These control signals light the segment of an electronic gauge 12 in replay to variously sensed levels of parameters and also light an indicator light 14 in replay to the defect or alarm state of a system. Digital and identification displays 26, 27 instruct proper values.