Most models of the Mercedes-Benz CLK 320 are equipped with a service reminder system that displays a notification light on the control panel when service is due. The on-board computer tracks driving conditions to determine when to illuminate the service reminder light. The service technician at the Mercedes-Benz dealer or garage will reset the service light for you when he performs regular maintenance on the car. If you do your own maintenance, you can turn the light off yourself.
Turn the ignition switch on. Do not start the engine.
Press the information menu button on the left of the steering wheel repeatedly until the total mileage is displayed.
Press the up- or down-arrow button on the left of the steering wheel until the service light is displayed.
Press and hold the reset button until a confirmation message appears on the display. The reset button is located to the left of the odometer.
Press and release the reset button to confirm the reset. The service light turns off.