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. Turn the ignition to ACC OR ON, with the radio off.
2. Press and hold the TUNE DISP button on the radio for at least five seconds until SETTINGS is displayed.
3. Press the SEEK PTYPE or the SEEK PSCAN up or down arrow to scroll through the main menu.
4. Scroll until OIL LIFE appears on the display.
5. Press the 1 PREV or 2 NEXT button to enter the submenu. RESET will be displayed.
6. Press the TUNE DISP button to reset. A chime will be heard to verify the new setting and DONE will be displayed for one second.
7. Once the message has been reset, scroll until EXIT appears on the display.
8. Press the TUNE DISP button to exit programming. A chime will be heard to verify the exit.

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

1. Turn the ignition to ON, with the engine off.
2. Fully press and release the accelerator pedal three times within five seconds.

If the CHANGE ENGINE OIL message flashes, the system is reset. However, if it stays on , it did not reset. Repeat the procedure.