2005 Mercedes SL-Class Owner's Manual - Page 316

Operation Maintenance i If the battery supplying the vehicle's electrical consumers is disconnected, the days of disconnection will not be included in the count shown by the service indicator. To arrive at the true service deadline, you will need to subtract these days from the days shown in the service indicator. Do not confuse the service indicator with the engine oil level indicator :. Resetting the maintenance service indicator In the event that the maintenance service on your vehicle is not carried out by an authorized Mercedes-Benz Center, you can have the maintenance service indicator reset. The automotive maintenance facility carrying out the maintenance service will find the information for resetting the maintenance service indicator in the maintenance-relevant information for your vehicle. Such information is available either from an authorized Mercedes-Benz Center or directly from Mercedes-Benz. ! If the maintenance service indicator was inadvertently reset, have an authorized Mercedes-Benz Center correct it. Only reset if the proper service has been performed. Resetting the system without performing proper service as called for by the maintenance service indicator will result in engine damage not covered by the Mercedes-Benz Limited Warranty. 314