Hydraulic Unit Solenoid Valves (Inlet/Outlet); Pressurized Brake Fluid Circuit - Suzuki 2006 GSF1200AK6 Supplementary Service Manual

HYDRAULIC UNIT SOLENOID VALVES (INLET/OUTLET)

The solenoid valves switch the brake fluid circuit to one of three positions (increasing, decreasing and main-
taining pressure) according to the signal that is output from the ABS control unit. As the ABS control unit
energize the coil, the valve compresses its spring and open/close the circuit.
When ABS is not activated,
Pressure-increasing mode
OUT/V
(Closed) (Opened)
Coil
Valve
Spring
Reservoir
Brake
caliper
Normal
position

PRESSURIZED BRAKE FLUID CIRCUIT

The brake fluid circuit of the ABS is divided into two systems: one for the front wheel and one for the rear
wheel. Both the front and rear brake systems are the same.
WHEN NOT OPERATING THE ABS (WHEN THE ABS IS NOT ACTIVATED OR AN ABS MALFUNCTION
HAS OCCURRED)
Brake fluid pressure-increasing mode
When the ABS is not activated, the solenoid valve coils are not energized (no signal is sent from the ABS
control unit). In this case, the inlet valve is open and the outlet valve is closed. The pressurized brake fluid
travels from the master cylinder to the brake caliper through the opened inlet valve.
Motor:
OFF
Pump
Reservoir
Pressure-maintaining mode
IN/V OUT/V
(Closed)
Valve
Valve
Reservoir
Master
cylinder
Normal Normal
position position
Brake operation
Inlet:
OFF
Solenoid valve
Outlet:
OFF
IN/V
(Closed)
Coil
Valve
Spring
Brake Master
Reservoir
caliper cylinder
Energized
position
Fluid pressure
at brake caliper
Brake
caliper
GSF1200AK6/SAK6 ('06-MODEL)
Pressure-decreasing mode
OUT/V IN/V
(Opened) (Closed)
Coil
Valve
Valve
Spring
Master
Brake
cylinder
caliper
Energized
Energized
position
position
OUT/V: Outlet solenoid valve
IN/V: Inlet solenoid valve
Signal Fluid circuit
IN/V OFF Open
OUT/V OFF Close
Time
11