With engine running at idle and the transmission in NEUTRAL, depress the brake pedal and hold a constant foot pressure. If the pedal gradually falls away with the constant pressure, the hydraulic system may be leaking. Perform a visual check to confirm any suspected leak.

First, check the master cylinder fluid levels. While a slight drop in reservoir level does result from normal lining wear, an abnormally low level in either reservoir indicates a leak in the system. Refer to Master Cylinder Diagnosis . Note that the system may appear to pass this test but still have slight leakage.

Next, check for possible fluid leaks at the brake pipe and brake hose connections. If any signs of leakage are found, replace the pipe or hose. Also inspect the connecting brake component to determine if it is damaged and should be rebuilt or replaced. Finally, check the caliper boots for leaks. If any fluid appears to be leaking, rebuild or replace the assembly.