1996 Buick LeSabre Owner's Manual - Page 122

When to change your oil depends on driving habits and conditions because these directly affect engine speed, coolant temperature and vehicle speed. Because of this, the CHANGE OIL SOON light may come on as early as 2,000 miles (3 218 km) or less for harsh circumstances. The CHANGE OIL SOON light is lit for fiveseconds as a bulb check each time the ignition key is turned to the RUN position. It will stay on for 60 seconds once 90% of the oil lifehas been used and each time the engine is started after that. If the CHANGE OIL SOON light is on continuously, there is a problem with the Oil Life Monitor System and service is required. After changing the erzgine oil, the system should he reset. This will cause the CHANGE OIL SOON light to be lit for abulb check period of three seconds. The reset button is in the glove box. With the ignition key in the RUN position, push the reset button, hold it in for at least five seconds but not more than 60 seconds. After five seconds,the CHANGE OIL SOONlight wiIl flash four times and then go off. This indicates that the Oil Life Monitor System has been reset. 2-66