Brake Master Cylinder - Bypass Condition Test

1. Check the brake hydraulic system for leaks or insufficient brake fluid. Repair as necessary.
2. Observe the brake fluid level in the brake master cylinder reservoir as the brake pedal is slowly pressed and quickly released. If the brake fluid level rises when the brake pedal is pressed and drops when the brake pedal is released, but the net brake fluid level remains unchanged, the brake master cylinder is bypassing. Repair or replace the brake master cylinder.