Cadillac 1993 Fleetwood Owners Literature page 145

If it doesn't come on, have it repaired. If the light comes on and stays on,
your engine oil level is too low. Check your oil level and add enough oil
to bring the engine oil level up to the proper level. See "Engine Oil" in
the Index.
Change Oil Light
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H
E
This light will come on
for .a few seconds as
you first start your
engine. The light will
also come on following
engine start up for 20
seconds when the
engine oil needs
changing.
See "Oil Life Indicator" in the Index.
Door Ajar Light (Option)
This light will come on
if a door is not
completely closed.
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