How to Reset a Mercedes Service Warning Light

1. Insert the key into the ignition. Turn the ignition switch to 'ON' but do not start the engine.
2. Press the up or down arrow button on the left side of the steering wheel until 'Service Interval Reset' is displayed on the instrument panel.
3. Press and hold the 'R/Reset' button on the instrument panel for at least three seconds until the service warning light resets on the display.