Hydraulic System: Testing and Inspection

Test Procedure

With the engine running at idle and the shift lever in "neutral" (N), depress the brake pedal and hold a constant foot pressure on the pedal. If the pedal gradually falls away with constant pressure, the hydraulic system may be leaking. Check the following visually to confirm a suspected leaks.

Master Cylinder Fluid Levels. While a slight drop in the levels occurs with normal lining wear, an abnormally low level, resulting in illumination of the "BRAKE" warning lamp, may mean a leak in the system. The system may be leaking internally or externally. Refer to Brakes / System Diagnosis for diagnosis of possible master cylinder leaks. (The system may appear to pass this test, but still have slight leakage.) Testing and Inspection

Brake Hose and Pipe Connections. If leakage is found, verify torque of fasteners and/or replace the hose or pipe.

Connecting Brake Components. Inspect for damage, and rebuild or repalace as needed.

Caliper. If leakage is found, rebuild or replace the assembly.

Additional Checks. Also, check the service brake pedal travel, brake adjustment and parking brake adjustment.