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Component Replacement
Below are the steps for the pressure fill, bleed process and using the WABCO TOOLBOX™ Software
version 12.7 to bleed the hydraulic brake system and SmartTrac™ ABS Module.
The WABCO TOOLBOX™ Software version 12.7 and beyond will support the following bleed
procedure.
1. Apply the parking brake and block the tires.
2.
Fill the pressure bleeder with new DOT 3 or DOT 4 hydraulic brake fluid. Refer to the vehicle
specifications to determine which fluid to use.
3. Follow the vehicle manufacturer’s instructions to connect the pressure bleeder to the brake master
cylinder reservoir.
4.
Set the filling pressure to 20 to 30 psi (1.5 to 2.0 bar). Do not exceed 30 psi pressure or damage to the
master cylinder reservoir may occur.
5.
Turn on the bleed equipment until the fluid level in the reservoir reaches the max fill line.
6.
Release pressure for three to five seconds. Apply pressure for five to 10 seconds.
7.
Repeat Step 5 and Step 6 approximately 10 times. If necessary, add fluid to the reservoir, making sure
that the fluid does not fall below the minimum level. After releasing the pressure, air bubbles may rise
up into the reservoir.
Repeatedly verify that the fluid in the reservoir does NOT fall below the minimum level. Add
brake fluid when necessary.
8. Start the bleeding procedure of all four wheel ends of the brake system by starting with the bleeder
fitting farthest from the SmartTrac™ module (typically the right rear).
Ensure the reservoir is filled with brake fluid to the MAX level and set the filling pressure to 20 to
30 psi (1.5 to 2.0 bar).
Place a wrench on the brake actuator bleeder fitting and then attach a length of clear plastic tubing
to the bleeder fitting. Verify that the tube fits snugly.
The tools, tubing and container used for bleeding should be brake fluid safe and must be able
to withstand the effects of brake fluid.
