Brake System External Leak Inspection
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CAUTION:
Refer to Brake Fluid Irritant Caution
.
NOTE:
Refer to Brake Fluid Effects on Paint and Electrical Components Notice
.
- In order to inspect for external brake fluid leaks, first check the fluid level in the master cylinder.
While a slight brake fluid level drop can be considered a normal condition due to brake lining wear, a very low level may indicate a brake fluid leak in the hydraulic system.
- If the fluid level is abnormally low, adjust the brake fluid level. Refer to Master Cylinder Reservoir Filling (JD9, JH6) or Master Cylinder Reservoir Filling (Two-mode Hybrid) .
- Start the engine and allow it to idle.
- Apply constant, moderate foot pressure to the brake pedal.
If the brake pedal gradually falls away while under foot pressure, there may be a brake fluid leak.
- Turn OFF the ignition.
- Visually inspect the following brake system components for brake fluid leaks, excessive corrosion, and damage. Give particular attention to all brake pipe and flexible hose connections to ensure that there are not any slight brake fluid leaks - even though the brake pedal may feel firm and hold steady:
- Master cylinder brake pipe fittings
- All brake pipe connections
- Brake pipes
- Brake hoses and connections
- Brake calipers and/or wheel cylinders, if equipped
- While slight dampness around the master cylinder reservoir can be considered acceptable, brake fluid leaking from any of the brake system components requires immediate attention. If any of these components exhibit signs of brake fluid leakage, repair or replace those components. After the repair or replacement, reinspect the hydraulic brake system to assure proper function.