Valve Solenoid - Pressure Hold

The "Pressure Hold Mode" activates the selected wheel circuit Hold valve placing it in the pressure hold position. When in the pressure hold position, the valve will not allow master cylinder pressure to be delivered to the hydraulic wheel circuit. This is done under actual operating conditions because the EBCM/EBTCM has determined that the wheel is moving too slowly, so it holds additional master cylinder pressure from it in an attempt to allow it to rotate at an appropriate speed. The Scan Tool commands the valve to close, which should allow the technician to spin the wheel even though an assistant is applying pressure to the brake pedal. Perform the test as follows:
1. Ignition "OFF."
2. Install the Scan Tool.
3. Turn ignition to "RUN."
4. Raise vehicle such that wheels are about six inches off the floor with the transmission in neutral.
5. Select Valve Solenoid Test. Have an assistant command "HOLD PRESSURE" with the Scan Tool.
6. Have the assistant press and hold the brake pedal.
7. Attempt to move the wheel being tested by hand; it should move even though the assistant is applying pressure to the brake pedal. The front wheels may be difficult to turn by hand, but can be moved if the system is working properly.