When the system has calculated that oil life has been diminished, it will indicate that an oil change is necessary. A CHANGE ENGINE OIL SOON message will come on. Change the engine oil as soon as possible within the next 600 miles (1000 km). It is possible that, if driving under the best conditions, the oil life may not indicate that an oil change is necessary for over a year. However, the engine oil and filter must be changed at least once a year and at this time the system must be reset.

If the system is ever reset accidentally, change the engine oil at 3000 miles (5000 km) since last oil change.

Follow this procedure to reset the GM Oil Life System™:

1. Press the up or down arrow to scroll the driver information center (DIC) to show OIL LIFE.
2. Once the ENGINE OIL LIFE menu item is highlighted, press and hold the RESET button until the percentage shows 100%. Repeat the steps if the percentage does not return to 100.
3. Turn the key to OFF.

If the CHANGE OIL NOW message comes back when you start the vehicle, the engine oil life system has not reset. Repeat the procedure.