Solenoid Test - Pressure Release

This test activates the selected hydraulic wheel circuit outlet valves, placing them in the pressure reduce position. When in the pressure reduce position, the valve will allow wheel caliper pressure to be returned to the master cylinder circuit. This Is done under actual operating conditions because the EBCM has determined that the wheel is moving too slowly, and holding additional master cylinder pressure from it has not allowed it to rotate at an appropriate speed. The scan tool commands the valves to these positions which should allow the technician to spin the wheel even though an assistant is applying pressure to the brake pedal.

Perform the following test:
1. Turn OFF the ignition.
2. Install a scan tool.
3. Turn ON the ignition, with the engine OFF.
4. Raise the vehicle. Refer to Vehicle Lifting. Ensure that all of the wheels are about 15 cm (6 inch) off of the floor.
5. Place the gear selector in the NEUTRAL position.
6. Select the Special Functions from the DRP/ABS/TCS/TIM/VSES menu.
7. Select the Solenoid Test. Have an assistant command the Outlet Valve Solenoid of the appropriate wheel using the scan tool.
8. Have the assistant press and hold the brake pedal.
9. Attempt to move the wheel being tested by hand. The wheel should move even though the assistant is applying pressure to the brake pedal. The front wheels may be difficult to turn by hand, but may be moved if the system is working properly.