Oldsmobile 2003 Silhouette Owner's Manual page 201

Brake System Warning Light
When the ignition is on, the brake system warning
light will come on when you set your parking
brake. The light will stay on if your parking brake
doesn't release fully. If it stays on after your parking
brake is fully released, it means you have a brake
problem.
Your vehicle's hydraulic brake system is divided
into two parts. If one part isn't working, the other
part can still work and stop you. For good braking,
though, you need both parts working well.
If the warning light comes on, there could be a
brake problem. Have your brake system inspected
right away.
BRAKE
United States Canada
This light should come on briefly when you turn
the ignition key to RUN. If it doesn't come on then,
have it fixed so it will be ready to warn you if
there's a problem.
If the light comes on while you are driving, pull off
the road and stop carefully. You may notice that the
pedal is harder to push. Or, the pedal may go
closer to the floor. It may take longer to stop.
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