2011 Mercedes CL-Class Owner's Manual - Page 382

380 Warning and indicator lamps in the instrument cluster Engine Problem Possible causes/consequences and M Solutions There may be a malfunction, for example: Rin Rin On-board computer and displays ; The yellow Check Engine warning lamp lights up while the engine is running. the engine management the fuel injection system Rin the exhaust system Rin the ignition system Rthe fuel system The emission limit values may have been exceeded and the engine may be breaking in emergency mode. X Have the vehicle checked as soon as possible at a qualified specialist workshop. i In some states/provinces, you are required by law to visit a qualified specialist workshop as soon as the Check Engine warning lamp lights up. If necessary, check whether this is the case in the state/province you are in. The yellow reserve fuel The fuel system pressure is too low. The fuel filler cap is not closed warning lamp flashes correctly or the fuel system is leaking. while the engine is X Check that the fuel filler cap is correctly closed. running. X If the fuel filler cap is not correctly closed: close the fuel filler cap. X If the fuel filler cap is closed: visit a qualified specialist workshop. The yellow reserve fuel The amount of fuel in the tank has dropped into the reserve range. warning lamp lights up X Refuel at the nearest gas station. while the engine is running.