2008 Mercedes S-Class Owner's Manual - Page 439

Controls in detail Driving systems The most likely cause for a malfunctioning system is a dirty sensor (located behind the hood grille), especially at times of snow and ice or heavy rain. In such a case, DISTRONIC Plus will switch off, and the message: "DISTRONIC PLUS currently unavailable See Oper. Manual" appears in the multifunction display. For cleaning and care of the DISTRONIC Plus sensor, see "Cleaning the DISTRONIC Plus*/ PRE-SAFE® Brake* system sensors (USA only)" ( page 589). i If the message: "DISTRONIC PLUS currently unavailable See Oper. Manual" disappears during driving and the last speed stored flashes for approximately 5 seconds, the dirt (e.g. slush) has dissolved; DISTRONIC Plus is again available. Turns and bends Another cause might be that the radar sensors have been manually switched off in the instrument cluster control system. Please verify that the radar sensors are switched on ( page 282). In turns or bends, DISTRONIC Plus may not detect a moving vehicle in front, or it may detect one too soon. This may cause your vehicle to brake late or unexpectedly. 438