C-Monitor Final filter monitoring system, oil change and technical interface. The interface consists of an LCD display, a button and two indicators. The decimal points next to the digits are indicator lights to indicate alarms or warnings in progress. Each dot is associated with an explanatory icon. The icon indicates an alarm condition while the symbol indicates normal operation. Press the button to scroll through the different functions of the menu. When pressed, the function is displayed and after two 2 seconds the corresponding data is displayed.