2003 Mercedes S-Class Owner's Manual - Page 294

Practical hints What to do if ...? Problem Possible cause The yellow "CHECK ENGINE" malfunction indicator lamp comes on while driving. There is a malfunction in: The fuel management system The ignition system The emission control system Systems which affect emissions Such malfunctions may result in excessive emissions values and may switch the engine to its limp-home (emergency operation) mode. The fuel cap is not closed tightly. Your gas tank is empty. Suggested solution Have the vehicle checked as soon as possible by an authorized Mercedes-Benz Center. An on-board diagnostic connector is used by the service station to link the vehicle to the shop diagnostics system. It allows the accurate identification of system malfunctions through the readout of diagnostic trouble codes. It is located in the front left area of the footwell next to the parking brake pedal. Close the fuel cap. After refuelling, start the engine three or four times in succession. The limp-home mode is canceled. You do not need to have your vehicle checked. The yellow fuel tank reserve warning lamp lights up while driving. The fuel level has gone below the reserve mark. The warning lamp reminds you to fasten seat belts. Refuel at the next gas station ( page 261). Fasten your seat belt. ? < The red seat belt warning lamp blinks for a brief period after starting the engine. 294