Nissan X-Trail 32. Manual - part 142

BRC-34

< SYSTEM DESCRIPTION >

[WITH VDC (ESP)]

SYSTEM

During pressure front LH brake holds

• Since the cut valve 2 and the suction valve 2 are closed, the front LH brake, master cylinder, and reservoir

are blocked. This maintains fluid pressure applied on the front LH brake. The pressurization for the right
brake is controlled separately from the left brake.

During pressure rear RH brake holds

• Since the cut valve 2 and the suction valve 2 are closed, the rear RH brake, master cylinder, and reservoir

are blocked. This maintains fluid pressure applied on the rear RH brake. The pressurization for the left brake
is controlled separately from the right brake.

During pressure rear LH brake holds

• Since the cut valve 1 and the suction valve 1 are closed, the rear LH brake, master cylinder, and reservoir

are blocked. This maintains fluid pressure applied on the rear LH brake. The pressurization for the right
brake is controlled separately from the left brake.

VDC Function, TCS Function, Brake Limited Slip Differential (BLSD) Function, Brake Assist Function, Brake force
distribution Function, hill start assist Function and Advanced hill descent control Function (4WD Models with Gaso-
line Engine) are in Operation (During Pressure Decrease)

During pressure front RH brake decreased

• Since the suction valve 1 and the ABS OUT valve close and the cut valve 1 and the ABS IN valve open, the

fluid pressure applied on the front RH brake is reduced by supplying the fluid pressure to the master cylinder
via the ABS IN valve and the cut valve 1. The pressurization for the right brake is controlled separately from
the left brake.

JSFIA1737GB

Component parts

Not activated

When pressure decrease

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 brake (fluid pressure)

—

Pressure decreases

SYSTEM

BRC-35

< SYSTEM DESCRIPTION >

[WITH VDC (ESP)]

C

D

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G

H

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M

A

B

BRC

N

O

P

During pressure front LH brake decreased

• Since the suction valve 2 and the ABS OUT valve close and the cut valve 2 and the ABS IN valve open, the

fluid pressure applied on the front LH brake is reduced by supplying the fluid pressure to the master cylinder
via the ABS IN valve and the cut valve 2. The pressurization for the left brake is controlled separately from
the right brake.

During pressure rear RH brake decreased

• Since the suction valve 2 and the ABS OUT valve close and the cut valve 2 and the ABS IN valve open, the

fluid pressure applied on the rear RH brake is reduced by supplying the fluid pressure to the master cylinder
via the ABS IN valve and the cut valve 2. The pressurization for the right brake is controlled separately from
the left brake.

During pressure rear LH brake decreased

• Since the suction valve 1 and the ABS OUT valve close and the cut valve 1 and the ABS IN valve open, the

fluid pressure applied on the rear LH brake is reduced by supplying the fluid pressure to the master cylinder
via the ABS IN valve and the cut valve 1. The pressurization for the left brake is controlled separately from
the right brake.

Component Parts and Function

VALVE OPERATION (ABS FUNCTION)

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

Component parts

Function

Pump

• Pressure the brake fluid and send.
• Returns the brake fluid reserved in reservoir to master cylinder by reducing pressure.

Motor

Activates the pump 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.

Suction valve 1
Suction valve 2

Supplies the brake fluid from master cylinder to the pump.

ABS IN valve

Switches the fluid pressure line to increase or hold according.

ABS OUT valve

Switches the fluid pressure line to increase, hold or decrease according.

return check valve

Returns the brake fluid from each brake to master cylinder by bypassing orifice of each valve when 
brake is released.

Reservoir

Temporarily reserves the brake fluid drained from each brake, so that pressure efficiently decreases 
when decreasing pressure of each brake.

Pressure sensor

Detects the brake fluid pressure and transmits signal to ABS actuator and electric unit (control unit).

BRC-36

< SYSTEM DESCRIPTION >

[WITH VDC (ESP)]

SYSTEM

When Brake Pedal is Applied

During pressure front RH brake increases

• When the cut valve 1 and the ABS IN valve opens, brake fluid is supplied to the front RH brake from the

master cylinder through the ABS IN valve. Brake fluid does not flow into the reservoir because the ABS OUT
valve is closed.

During pressure front LH brake increases

• When the cut valve 2 and the ABS IN valve opens, brake fluid is supplied to the front LH brake from the mas-

ter cylinder through the ABS IN valve. Brake fluid does not flow into the reservoir because the ABS OUT
valve is closed.

During pressure rear RH brake increases

• When the cut valve 2 and the ABS IN valve opens, brake fluid is supplied to the rear RH brake from the mas-

ter cylinder through the ABS IN valve. Brake fluid does not flow into the reservoir because the ABS OUT
valve is closed.

During pressure rear LH brake increases

• When the cut valve 1 and the ABS IN valve opens, brake fluid is supplied to the rear LH brake from the mas-

ter cylinder through the ABS IN valve. Brake fluid does not flow into the reservoir because the ABS OUT
valve is closed.

JSFIA1738GB

Component parts

Not activated

When pressure increases

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 brake (fluid pressure)

—

Pressure increases

SYSTEM

BRC-37

< SYSTEM DESCRIPTION >

[WITH VDC (ESP)]

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BRC

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When ABS Function is in Operation (During Pressure Increases)

During pressure front RH brake increases

• Brake fluid is supplied to the front RH brake from the master cylinder through the cut valve 1 and the ABS IN

valve. Since the suction valve 1 and the ABS OUT valve is closed, the fluid does not flow into the reservoir.
The amount of brake fluid supplied to the front RH brake from the master cylinder is controlled according to
time that the ABS IN valve is not energized (time that the ABS IN valve is open).

During pressure front LH brake increases

• Brake fluid is supplied to the front LH brake from the master cylinder through the cut valve 2 and the ABS IN

valve. Since the suction valve 2 and the ABS OUT valve is closed, the fluid does not flow into the reservoir.
The amount of brake fluid supplied to the front LH brake from the master cylinder is controlled according to
time that the ABS IN valve is not energized (time that the ABS IN valve is open).

During pressure rear RH brake increases

• Brake fluid is supplied to the rear RH brake from the master cylinder through the cut valve 2 and the ABS IN

valve. Since the suction valve 2 and the ABS OUT valve is closed, the fluid does not flow into the reservoir.
The amount of brake fluid supplied to the rear RH brake from the master cylinder is controlled according to
time that the ABS IN valve is not energized (time that the ABS IN valve is open).

During pressure rear LH brake increases

• Brake fluid is supplied to the rear LH brake from the master cylinder through the cut valve 1 and the ABS IN

valve. Since the suction valve 1 and the ABS OUT valve is closed, the fluid does not flow into the reservoir.

JSFIA1738GB

Component parts

Not activated

When pressure increases

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 brake (fluid pressure)

—

Pressure increases