2009 Mercedes S-Class Owner's Manual - Page 333

Practical hints What to do if ... Brake Problem - The yellow ABS indicator lamp comes on while the engine is running. Possible cause/consequence Suggested solutions X Continue driving with added caution. Wheels may lock during hard The ABS has detected a malfunction and switched off. braking, reducing steering capability. The BAS, ESP®, EBP and PREX Read and observe messages that may appear in the multifunction SAFE® are also switched off (see display (Y page 295). messages in multifunction X Have the system checked at an authorized Mercedes-Benz Center display). as soon as possible. The brake system is still Failure to follow these instructions increases the risk of an accident. functioning normally but without the systems specified above available. If the ABS control unit is malfunctioning, other systems such as the navigation system or the automatic transmission may also be malfunctioning. - The yellow ABS indicator lamp comes on while the engine is running. ; (USA only) 3 (Canada only) The red brake warning lamp comes on while driving and an acoustic warning sounds. The ABS has switched off due to When the voltage is above the required value again, the ABS is insufficient power supply. operational again and the ABS indicator lamp should go out. The battery might not be charged X If the ABS indicator lamp does not go out: Have the alternator and sufficiently. the battery checked. You are driving with the parking brake engaged. X Release the parking brake. Z 331