Vacuum Function Inspection

WARNING: This page is about a different car, the 2018 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

Start the engine.
Stop the engine after driving the vehicle for 1-2 min.
Depress the brake pedal with normal force.
If the first pedal stroke is long and becomes shorter with subsequent strokes, the unit is normal.
- If a problem is found, inspect for damage to or improper installation of the check valve and vacuum hose. After repairing, inspect again.