The vehicle brake system consists of two hydraulic circuits. If one circuit is not working, the remaining circuit can still work to stop the vehicle. For normal braking performance, both circuits need to be working.
If the warning light comes on, there is a brake problem. Have the brake system inspected right away.

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The brake indicator light should come on briefly as the engine is started. If it does not come on have the vehicle serviced by your dealer.
WARNING
The brake system might not be working properly if the brake system warning light is on.
Driving with the brake system warning light on can lead to a crash. If the light is still on after the vehicle has been pulled off the road and carefully stopped, have the vehicle towed for service.
If the light comes on while driving, a chime sounds. Pull off the road and stop. The pedal might be harder to push or go closer to the floor.
It might also take longer to stop.
If the light is still on, have the vehicle towed for service.
Malfunction Indicator Lamp
Antilock Brake System (ABS) Warning LightDual Phase Steel
This information provides repair recommendations and general guidelines for
steel classified as Dual Phase Steel (Dual Phase Steel with a
tensile strength up to and including 800 MPa), also known as DP.
General Motors recommends the following when repairing or replacing this type of
steel du ...
Scheduling Service Appointments
When the vehicle requires warranty service, contact your dealer and request an
appointment. By scheduling a service appointment and advising the service consultant
of your transportation needs, your dealer can help minimize your inconvenience.
If the vehicle cannot be scheduled into the service ...
Steering Angle Sensor Calibration Warning
Warning: For vehicles with electric power steering (EPS) and without
a vehicle stability enhancement program, the steering angle sensor
MUST always be calibrated after the battery has been disconnected. Failure to
calibrate the steering angle sensor could limit the operation
of the EPS system ...