See also:

Brake fluid
The fluid level will drop slowly as the brakes wear, and will rise when the brake components are replaced. Fluid levels between the MIN and MAX lines are within the normal operating range; ...

Troubleshooting
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Windows and wiper blades
The windshield, rear and side windows and the wiper blades should be cleaned regularly. If the wipers do not wipe properly, substances on the vehicle’s glass or the wiper blades may be the cause. ...