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.
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.

This light should come on briefly when the ignition is turned to ON. If it does not come on then, have it fixed so it will be ready to warn if there is a problem.
When the ignition is on, the brake system warning light will also come on when the parking brake is set. The light will stay on if the parking brake does not fully release. If it stays on after the parking brake is fully released, it means there is a brake problem.
If the light comes on while driving, carefully pull off the road and stop. The pedal may be harder to push or may go closer to the floor. It may take longer to stop. If the light is still on, have the vehicle towed for service. See Towing the Vehicle.
Service Vehicle Soon Light
Antilock Brake System (ABS) Warning LightParking Brake Cable Replacement (Drum Brake)
Removal Procedure
Remove the front floor console. Refer to Front Floor Console Replacement.
Ensure that the parking brake lever is in the fully released position.
Using ONLY HAND TOOLS, remove the adjusting nut (1) from the end of
the front park bra ...
Air Conditioning O-Ring Seal Replacement
Removal Procedure
Disassemble the A/C refrigerant components. Refer to the appropriate
repair procedure
Note: Cap or tape the open A/C refrigerant components immediately
to prevent system contamination.
Cap or tape the A/C refrigerant components.
...
Heating and Air Conditioning System Description and Operation
Engine Coolant
Engine coolant is the key element of the heating system. The engine thermostat
controls the normal engine operating coolant temperature. Coolant pumped out
of the engine enters the heater core through the inlet heater hose. The air
flowing through the HVAC module abs ...