Buick Century 2003 Owner's Manual page 141

Low Oil Level Light
If the light does not come on briefly, have it fixed so it
will be ready to warn you if there's a problem.
If the light stays on, stop the vehicle on a level surface
and turn the engine off. Check the oil level using the
engine oil dipstick. See Engine Oil on page 5-13 . If the
light does not come on briefly, have the low oil level
sensor system repaired so it will be ready to warn you if
there's a problem.
The oil level monitoring system only checks oil level
during the brief period between key on and engine
crank. It does not monitor engine oil level when
the engine is running. Additionally, an oil level check is
only performed if the engine has been turned off for
a considerable period of time, allowing the oil normally
in circulation to drain back into the oil pan.
If your vehicle is equipped
with an oil level monitoring
system, the LOW OIL
light will come on briefly
when the ignition key
is turned on.
Change Engine Oil Light
If the CHANGE OIL SOON light comes on and stays on
after you start the engine, have the oil changed.
For additional information, see "When to Change Engine
Oil (GM Oil Life System)" under Engine Oil on page 5-13 .
To reset the CHANGE OIL SOON light, see "How to
Reset the System" under Engine Oil on page 5-13 .
The CHANGE OIL SOON
light should come on
briefly as a bulb check
when you start the engine.
If the light doesn't come
on, have it serviced.
3-35