1998 Buick LeSabre Owner's Manual - Page 133

After changing the engine oil, the system should be reset. This will cause the CHANGEOIL SOON light to be lit for a bulb check period of three seconds. Referto "Engine Oil" inthe Index to determine what type of oil to use. Fuel Gage Q' \ \ \ E Standard Cluster Gage Cluster The reset button is in the glovebox. With the ignition key in RUN, push the reset button, hold it in for at least five seconds but not more than 60 seconds. After five seconds, the CHANGE OIL SOON light flash four will times and then go off. This indicates that the Oil Life Monitor System has been reset. Your fuel gage shows about how much fuel is in your tank. It works only when the engine is on. When the indicator nears EMPTY (E), you still have a little fuel left. You need to get more fuel right away. 2-69