Every model year of the Mercedes ML320 is equipped with an on-board computer that tracks driving and engine conditions to determine when service would be needed, such as oil changes. When the computer does determine that service is needed, an indicator message appears on the control panel. A Mercedes-Benz dealer will reset the service indicator when they perform the service. If you perform the service yourself, you can manually reset the service indicator.
Turn the ignition switch using your key to the "II" position.
Press the trip odometer reset button twice within one second. This must be done within four seconds of moving the ignition to the "II" position. This causes the car to enter reset mode.
Turn the ignition switch to the "0" position.
Press and hold the trip odometer reset button.
Turn the ignition switch to the "II" position.
Release the trip odometer reset button when the service indicator resets and a chime sounds. Turn the ignition switch off.