It means it is time to change the oil or perform some other maintenance task check the owners manual for specifics at the posted mileage.
To reset the maintenance light, have the key out of the ignition. Then press and hold the trip reset button, insert the key and turn the ignition to the on position while holding the trip reset button in. After 10 to 30 seconds, the maintenance light should start to flash and when it stops, the light is reset. After the light is reset, the maintenance light should illuminate for 1-2 seconds when the key is first turned on