Brake fluid transfers force from the brake pedal to the braking system. Low fluid can signal normal pad wear, a leak, or another issue—so topping it off without inspection may hide a problem.
Check the right way
Use the owner’s manual to locate the reservoir and specified fluid type. Keep dirt and moisture out of the reservoir.
When to seek help
A low level, red brake warning, soft pedal, or visible leak needs professional inspection. Never use a fluid type not specified by the vehicle manufacturer.