The Mercedes Benz GL450 sport-utility vehicle is equipped with a service indicator warning that is displayed at regular mileage intervals when maintenance is needed. Service technicians reset the light during regular maintenance so it turns off until service is next required. You can manually reset the service indicator light when you maintain your vehicle. These instructions apply to the 2011 GL450. The sequence is the same or similar for previous model years.
Insert the key in the ignition. Move the ignition switch to position I.
Press the left or right menu button on the display until the mileage is displayed on the screen. The menu buttons are located directly above the display screen.