Brake Release (fluid return)

At the end of the antilock stop, when the driver releases the brake pedal, the motor will remain on for a short time to help drain any fluid left in the Low Pressure Accumulator (LPA). As the fluid drains back into the system, the spring force in the LPA pushes the piston to the home position. When the stoplamp switch closes, the Isolation (ISO) valve is turned off and fluid may return through the isolation orifice.