System Diagnosis - Hydraulic System Fluid Loss

1. Run the engine at idle.
2. Put the range selector lever in NEUTRAL.
3. Depress the brake pedal. Hold the brake pedal with constant foot pressure.
4. If the pedal gradually falls away with constant pressure, the brake hydraulic system may be leaking. Inspect the hydraulic system for any suspected leaks.
5. Inspect the master cylinder fluid level.
^ A slight drop in the master cylinder reservoir level results from normal pad wear. The reservoir may be as low as 25.4 mm (1.0 inch) from the top if the pads are worn. This condition is not abnormal.
^ An abnormally low level in the reservoir indicates a leak in the system. The brake hydraulic system may be leaking either internally or externally. Refer to Brake System Diagnosis (f). The system may appear to pass this test but still have a slight leakage. Symptom Related Diagnostic Procedures
6. Inspect the brake pipe and the brake hose connections for brake fluid leaks.
7. If any leaks are found, replace the hose or the pipe.
8. If any hoses or pipes are replaced, inspect the connecting brake component for damage. If damage is found, rebuild or replace the component.
9. Inspect the brake caliper boots and rear wheel cylinder boots for leaks.
10. If any leaks are found, rebuild or replace the part in question. Refer to Disc Brakes or Drum Brakes.