Mazda RX-8 2009 Service Highlights page 149

During ABS and EBD control
! During ABS and EBD control, when wheel lock-up is about to occur, the traction switch and stability control
solenoid valves are not energized, and the inlet and outlet solenoid valves are energized and controlled in three
pressure modes (increase, reduction or maintain), thereby adjusting brake fluid pressure. Brake fluid during
pressure reduction is temporarily stored in the reservoir and afterwards the pump motor operates the pump to
return the fluid to the master cylinder. (The following figure shows these conditions: right front wheel pressure
increased, left front wheel pressure maintained, and both rear wheels pressure decreased.)
Solenoid valve operation table
Traction control
solenoid valve
LF—RR RF—LR
During
Pressure
OFF (open)
increase
mode
During
pressure
OFF (open)
maintain
mode
During
pressure
OFF (open)
reduction
mode
Hydraulic circuit diagram
MASTER CYLINDER
TRACTION
CONTROL
SOLENOID
VALVE
STABILITY
CONTROL
SOLENOID
VALVE
INLET
SOLENOID
VALVE
OUTLET
SOLENOID
VALVE
PRESSURE
INCREASE
DYNAMIC STABILITY CONTROL
Stability control
solenoid valve
LF—RR RF—LR
OFF (closed)
OFF (closed)
OFF (closed)
P
RESERVOIR
OUTLET
LR
RF
SOLENOID
VALVE
PRESSURE
REDUCTION
Inlet solenoid valve
LF RF LR RR LF
OFF (open)
ON (closed)
ON (closed)
BRAKE FLUID
PRESSURE SENSOR
PUMP
PUMP
MOTOR
RESERVOIR
OUTLET
RR
SOLENOID
VALVE
PRESSURE
REDUCTION
Pump
Outlet solenoid valve
motor,
pump
RF LR RR
OFF (closed) Stopped
OFF (closed) Stopped
ON (open) Operating
TRACTION
CONTROL
SOLENOID
VALVE
STABILITY
CONTROL
SOLENOID
VALVE
INLET
SOLENOID
VALVE
OUTLET
LF
SOLENOID
VALVE
PRESSURE
MAINTAINED
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