Valve Operation

Each valve is operated and fluid pressure of brake caliper is controlled.

When Ordinary Brake Is Applied

Fig 1: Valve Operation Diagram (Ordinary Brake Applied)

Courtesy of NISSAN NORTH AMERICA, INC.

Name	Not activated	When depressing brake pedal
Cut valve 1	Power supply is not supplied (open)	Power supply is not supplied (open)
Cut valve 2	Power supply is not supplied (open)	Power supply is not supplied (open)
Suction valve 1	Power supply is not supplied (close)	Power supply is not supplied (close)
Suction valve 2	Power supply is not supplied (close)	Power supply is not supplied (close)
ABS IN valve	Power supply is not supplied (open)	Power supply is not supplied (open)
ABS OUT valve	Power supply is not supplied (close)	Power supply is not supplied (close)
Each caliper (fluid pressure)	-	Pressure increases

Front RH caliper

Pressurized brake fluid from accumulator is supplied to front RH caliper through master cylinder part, cut valve 1 and ABS IN valve.

Front LH caliper

Pressurized brake fluid from accumulator is supplied to front LH caliper through master cylinder part, cut valve 1 and ABS IN valve.

Rear RH caliper

Pressurized brake fluid from accumulator is supplied to rear RH caliper through master cylinder part, cut valve 2 and ABS IN valve.

Rear LH caliper

Pressurized brake fluid from accumulator is supplied to rear LH caliper through master cylinder part, cut valve 2 and ABS IN valve.

ABS Is Operating (When Pressure Increases)

Fig 2: ABS Valve Operation Diagram (When Pressure Increases)

Courtesy of NISSAN NORTH AMERICA, INC.

Name	Not activated	When Pressure Increases
Cut valve 1	Power supply is not supplied (open)	Power supply is supplied (close)
Cut valve 2	Power supply is not supplied (open)	Power supply is not supplied (open)
Suction valve 1	Power supply is not supplied (close)	Power supply is supplied (open)
Suction valve 2	Power supply is not supplied (close)	Power supply is not supplied (close)
ABS IN valve	Power supply is not supplied (open)	Power supply is not supplied (open)
ABS OUT valve	Power supply is not supplied (close)	Power supply is not supplied (close)
Each caliper (fluid pressure)	-	Pressure increases

Front RH caliper

Pressurized brake fluid from accumulator is supplied to front RH caliper through master cylinder part, cut valve 2, suction valve 1 and ABS IN valve.

Front LH caliper

Pressurized brake fluid from accumulator is supplied to front LH caliper through master cylinder part, cut valve 2, suction valve 1 and ABS IN valve.

Rear RH caliper

Pressurized brake fluid from accumulator is supplied to rear RH caliper through master cylinder part, cut valve 2 and ABS IN valve.

Rear LH caliper

Pressurized brake fluid from accumulator is supplied to rear LH caliper through master cylinder part, cut valve 2 and ABS IN valve.

ABS Is Operating (When Pressure Holds)

Fig 3: ABS Valve Operation Diagram (When Pressure Hold)

Courtesy of NISSAN NORTH AMERICA, INC.

Name	Not activated	When Pressure Increases
Cut valve 1	Power supply is not supplied (open)	Power supply is supplied (close)
Cut valve 2	Power supply is not supplied (open)	Power supply is not supplied (open)
Suction valve 1	Power supply is not supplied (close)	Power supply is supplied (open)
Suction valve 2	Power supply is not supplied (close)	Power supply is not supplied (close)
ABS IN valve	Power supply is not supplied (open)	Power supply is supplied (close)
ABS OUT valve	Power supply is not supplied (close)	Power supply is not supplied (close)
Each caliper (fluid pressure)	-	Pressure holds

Front RH caliper

ABS IN valve is close, fluid pressure of front RH caliper is holds.

Front LH caliper

ABS IN valve is close, fluid pressure of front LH caliper is holds.

Rear RH caliper

ABS IN valve is close and fluid pressure of rear RH caliper is holds.

Rear LH caliper

ABS IN valve is close and fluid pressure of rear LH caliper is holds.

ABS Is Operating (When Pressure Decreases)

Fig 4: ABS Valve Operation Diagram (When Pressure Decreases)

Courtesy of NISSAN NORTH AMERICA, INC.

Name	Not activated	When pressure decreases
Cut valve 1	Power supply is not supplied (open)	Power supply is supplied (close)
Cut valve 2	Power supply is not supplied (open)	Power supply is not supplied (open)
Suction valve 1	Power supply is not supplied (close)	Power supply is supplied (open)
Suction valve 2	Power supply is not supplied (close)	Power supply is not supplied (close)
ABS IN valve	Power supply is not supplied (open)	Power supply is supplied (close)
ABS OUT valve	Power supply is not supplied (close)	Power supply is supplied (open)
Each caliper (fluid pressure)	-	Pressure decreases

Front RH caliper

Being returned to reservoir tank through ABS OUT valve, fluid pressure of front RH caliper is decreased.

Front LH caliper

Being returned to reservoir tank through ABS OUT valve, fluid pressure of front LH caliper is decreased.

Rear RH caliper

Being returned to reservoir tank through ABS OUT valve, fluid pressure of rear RH caliper is decreased.

Rear LH caliper

Being returned to reservoir tank through ABS OUT valve, fluid pressure of rear LH caliper is decreased.

VDC Is Operating (When Pressure Increases)

Fig 5: VDC Valve Operation Diagram (When Pressure Increases)

Courtesy of NISSAN NORTH AMERICA, INC.

Name	Not activated	When pressure increases
Cut valve 1	Power supply is not supplied (open)	Power supply is supplied (close)
Cut valve 2	Power supply is not supplied (open)	Power supply is supplied (close)
Suction valve 1	Power supply is not supplied (close)	Power supply is supplied (open)
Suction valve 2	Power supply is not supplied (close)	Power supply is supplied (open)
ABS IN valve	Power supply is not supplied (open)	Only in wheel that the pressure is to be increased: Power supply is not supplied (open) Wheel other than the one that the pressure is to be increased: Power supply is supplied (close)
ABS OUT valve	Power supply is not supplied (close)	Power supply is not supplied (close)
Each caliper (fluid pressure)	-	Pressure increases (only in wheel that the pressure is to be increased)

Front RH caliper

Pressurized brake fluid from accumulator is supplied to front RH caliper through suction valve 2, suction valve 1 and ABS IN valve. When not increasing, ABS IN valve is closed and brake fluid is not supplied to front RH caliper.

Front LH caliper

Pressurized brake fluid from accumulator is supplied to front LH caliper through suction valve 2, suction valve 1 and ABS IN valve. When not increasing, ABS IN valve is closed and brake fluid is not supplied to front LH caliper.

Rear RH caliper

Pressurized brake fluid from accumulator is supplied to rear RH caliper through suction valve 2 and ABS IN valve. When not increasing, ABS IN valve is closed and brake fluid is not supplied to rear RH caliper.

Rear LH caliper

Pressurized brake fluid from accumulator is supplied to rear LH caliper through suction valve 2 and ABS IN valve. When not increasing, ABS IN valve is closed and brake fluid is not supplied to rear LH caliper.

VDC Is Operating (When Pressure Holds)

Fig 6: VDC Valve Operation Diagram (When Pressure Holds)

Courtesy of NISSAN NORTH AMERICA, INC.

Name	Not activated	When pressure holds
Cut valve 1	Power supply is not supplied (open)	Power supply is supplied (close)
Cut valve 2	Power supply is not supplied (open)	Power supply is supplied (close)
Suction valve 1	Power supply is not supplied (close)	Power supply is supplied (open)
Suction valve 2	Power supply is not supplied (close)	Power supply is supplied (open)
ABS IN valve	Power supply is not supplied (open)	Only wheel that the pressure is to be holds: Power supply is supplied (close) Wheel other than the one that the pressure is to be holds: Power supply is not supplied (open)
ABS OUT valve	Power supply is not supplied (close)	Power supply is not supplied (close)
Each caliper (fluid pressure)	-	Pressure holds (only wheel that the pressure is to be holds)

Front RH caliper

ABS IN valve is close, fluid pressure of front RH caliper is holds.

Front LH caliper

ABS IN valve is close, fluid pressure of front LH caliper is holds.

Rear RH caliper

ABS IN valve is close, fluid pressure of rear RH caliper is holds.

Rear LH caliper

ABS IN valve is close, fluid pressure of rear LH caliper is holds.

VDC Is Operating (When Pressure Decreases)

Fig 7: VDC Valve Operation Diagram (When Pressure Decreases)

Courtesy of NISSAN NORTH AMERICA, INC.

Name	Not activated	When pressure decreases
Cut valve 1	Power supply is not supplied (open)	Power supply is supplied (close)
Cut valve 2	Power supply is not supplied (open)	Power supply is supplied (close)
Suction valve 1	Power supply is not supplied (close)	Power supply is supplied (open)
Suction valve 2	Power supply is not supplied (close)	Power supply is supplied (open)
ABS IN valve	Power supply is not supplied (open)	Only in wheel that the pressure is to be decreased: Power supply is supplied (close) Wheel other than the one that the pressure is to be decreased: Power supply is not supplied (open)
ABS OUT valve	Power supply is not supplied (close)	Only in wheel that the pressure is to be decreased: Power supply is supplied (open) Wheel other than the one that the pressure is to be decreased: Power supply is not supplied (close)
Each caliper (fluid pressure)	-	Pressure decreases (only in wheel that the pressure is to be decreased)

Front RH caliper

Being returned to reservoir tank through ABS OUT valve, fluid pressure of front RH caliper is decreased.

Front LH caliper

Being returned to reservoir tank through ABS OUT valve, fluid pressure of front LH caliper is decreased.

Rear RH caliper

Being returned to reservoir tank through ABS OUT valve, fluid pressure of rear RH caliper is decreased.

Rear LH caliper

Being returned to reservoir tank through ABS OUT valve, fluid pressure of rear LH caliper is decreased.

Component Parts and Function

Component	Function
Pump	Operates the pump drive according to signals from ABS actuator and electric unit (control unit) by the motor.
Motor	Operates the motor drive according to signals from ABS actuator and electric unit (control unit).
Accumulator	The accumulator accumulates brake fluid conveyed by the motor and pump.
ABS IN valve	Increases, holds or decreases the fluid pressure of each caliper according to signals from ABS actuator and electric unit (control unit).
ABS OUT valve	Increases, holds or decreases the fluid pressure of each caliper according to signals from ABS actuator and electric unit (control unit).
Cut valve 1 Cut valve 2	Shuts off the ordinary brake line from master cylinder to signals from ABS actuator and electric unit (control unit).
Suction valve 1	Suction valve 1 switches the brake line to convey accumulator pressure to the front system, according to a signal transmitted from the ABS actuator and electric unit (control unit).
Suction valve 2	Suction valve 2 releases accumulator pressure, according to a signal transmitted from the ABS actuator and electric unit (control unit).
Accumulator pressure sensor	The accumulator pressure sensor detects brake fluid pressure accumulated in the accumulator and conveys the detected result to the ABS actuator and electric unit (control unit).
Master cylinder pressure sensor	Detects the brake fluid pressure of master cylinder part and transmits a signal to ABS actuator and electric unit (control unit).