The car is equipped with numerous light sources for optimal lighting of interior instruments and controls.Some of these are lit with the ignition ON (INT), others with the side lights on, others are dimmable in accordance with a rheostat-controlled adjustment strategy managed by the Body Computer.The Body Computer manages the lighting - with the side lights on - of:- cigar lighter and rear current socket;- controls on the front courtesy lightThe Body Computer manages (directly and via the door and boot node control units) the dimmed lighting of:- instrument panel and display;- auxiliary instrument- switches in the doors;- climate control system controls;- built-in radio-telephone-navigator unit;All the other controls are lit up when the ignition is on (INT), i.e. with the TEG inserted.A brightness sensor for the automatic adjustment (day/night) of the brightness of the instrument panel is built-in; it has the task of measuring the ambient light conditions and sending this information (daytime or nightime) to the Body Computer which, on comparing this information with the state of the side lights, selects the appropriate lighting configuration for the vehicle interior (daytime or nightime mode).With this information available, the behaviour of the instrument is as follows:- In "daytime" mode the display can be adjusted to 8 settings, the graphics are switched off, the index lighting is 100% and cannot be adjusted.- In "nightime" mode the display, the graphics and the indexes can be adjusted to 8 settings and the level set will be transmitted to the components that regulate the brightness (climate control display, radio display).This adjustment is made using the "MODE", "MODE +" and "MODE -" buttons located on the steering column switch unit; there are 8 different possible settings. (fom 30% to 100% of the maximum intensity). The level set by pressing the buttons is shown on the instrument panel display; the setting is also memorized and used later on.