Subaru 2002 Impreza Service Manual page 320

ANTI-LOCK BRAKE SYSTEM (ABS)
ABS
3. PRESSURE "HOLD" CONTROL (ABS ACTIVE)
The inlet solenoid valve is energized, so the inlet port is closed.
On the other hand, the outlet solenoid valve is de-energized, so the output port is also closed. In
this state, all the passages connecting the wheel cylinder, master cylinder and reservoir are
blocked. As a result, the fluid pressure in the wheel cylinder is held unchanged.
During this phase of ABS operation, the pump motor continues operating.
NOTE:
For simplicity of explanation, operation of the hydraulic control unit is represented by operation
of a single wheel circuit.
ABS-I 4