ABS System Description - ABS Modulator

The ABS modulator unit consists of the inlet solenoid valve, the outlet solenoid valve, the reservoir, the pump, and the pump motor. The hydraulic control has three modes of ABS action; pressure intensifying, pressure retaining, and pressure reducing.

Courtesy of HONDA, U.S.A., INC.

Mode	Inlet Solenoid Valve	Outlet Solenoid Valve	Brake Fluid
Pressure intensifying mode	open	closed	Master cylinder fluid is pumped out to the caliper.
Pressure retaining mode	closed	closed	Caliper fluid is retained by the inlet and outlet valves.
Pressure reducing mode	closed	open	Caliper fluid flows through the outlet valve to the reservoir. The motor pumps the reservoir fluid through the master cylinder.