Infiniti QX56 (Z62). Manual - part 132

COMPONENT PARTS

BRC-13

< SYSTEM DESCRIPTION >

[WITH VDC]

C

D

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G

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BRC

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Component Description

INFOID:0000000006222560

*1: Models with Advanced Driver Assistance System
*2: Models with 4WD system

D.

ABS warning lamp, brake warning 
lamp, VDC warning lamp, VDC OFF 
indicator lamp

E.

Back of spiral cable assembly

F.

Center console assembly

G.

Under center console assembly

H.

Rear wheel hub and bearing assem-
bly

Component

Reference/Function

ABS actuator and electric unit 
(control unit)

Motor/accumulator assembly

BRC-14, "ABS Actuator and Electric Unit (Control Unit)"

Motor relay

Actuator relay (main relay)

ABS IN valve

ABS OUT valve

Cut valve 1

Cut valve 2

Suction valve 1

Suction valve 2

Control pressure sensor

*1

Accumulator pressure sensor

Master cylinder pressure sensor

Wheel sensor

BRC-14, "Wheel Sensor and Sensor Rotor"

Stop lamp switch

BRC-15, "Stop Lamp Switch"

Steering angle sensor

BRC-15, "Steering Angle Sensor"

Yaw rate/side/decel G sensor

BRC-15, "Yaw Rate/Side/Decel G sensor"

Brake fluid level switch

BRC-15, "Brake Fluid Level Switch"

Parking brake switch

BRC-15, "Parking Brake Switch"

VDC OFF switch

BRC-15, "VDC OFF Switch"

ECM

Mainly transmits the following signals to ABS actuator and elec-
tric unit (control unit) via CAN communication.
• Accelerator pedal position signal
• Engine speed signal
Mainly receives the following signals from ABS actuator and 
electric unit (control unit) via CAN communication.
• Target throttle position signal

TCM

Mainly transmits the following signals to ABS actuator and elec-
tric unit (control unit) via CAN communication.
• Shift position signal
• Current gear position signal

Transfer control unit

*2

Mainly transmits the following signals to ABS actuator and elec-
tric unit (control unit) via CAN communication.
• Current 4WD mode signal

ABS warning lamp

BRC-16, "System Description"

Brake warning lamp

VDC warning lamp

VDC OFF indicator lamp

BRC-14

< SYSTEM DESCRIPTION >

[WITH VDC]

COMPONENT PARTS

ABS Actuator and Electric Unit (Control Unit)

INFOID:0000000006222561

Electric unit (control unit) is integrated with actuator and motor/accumulator assembly and comprehensively
controls VDC function, TCS function, ABS function, EBD function, hill start assist function or brake limited slip
differential function.

ELECTRIC UNIT (CONTROL UNIT)

• Brake fluid pressure, engine and transmission are controlled according to signals from each sensor.
• If malfunction is detected, the system enters fail-safe mode.

ACTUATOR

The following components are integrated with ABS actuator.

Motor/accumulator Assembly

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.

Motor Relay

Operates the motor ON/OFF according to signals from ABS actuator and electric unit (control unit).

Actuator Relay (Main Relay)

Operates each valve ON/OFF according to signals from ABS actuator and electric unit (control unit).

ABS IN Valve and 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 path 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).

Control Pressure Sensor (models with Advanced Driver Assistance System)

Detects the brake fluid pressure of brake caliper side and transmits a signal to 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).

Wheel Sensor and Sensor Rotor

INFOID:0000000006222562

NOTE:
• Wheel sensor and sensor rotor is integrated in wheel hub assembly.
• Never measure resistance and voltage value using a tester because sensor is active sensor.

COMPONENT PARTS

BRC-15

< SYSTEM DESCRIPTION >

[WITH VDC]

C

D

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BRC

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• Downsize and weight reduction is aimed. IC for detection portion

and magnet for sensor rotor are adopted.

• Power supply is supplied to detection portion so that magnetic field

line is read. Magnetic field that is detected is converted to current
signal.

• When sensor rotor rotates, magnetic field changes. Magnetic field

change is converted to current signals (rectangular wave) and is
transmitted to ABS actuator and electric unit (control unit). Change
of magnetic field is proportional to wheel speed.

Stop Lamp Switch

INFOID:0000000006222563

Detects the operation status of brake pedal and transmits converted electric signal to ABS actuator and elec-
tric unit (control unit).

Steering Angle Sensor

INFOID:0000000006222564

Detects the following information and transmits steering angle signal to ABS actuator and electric unit (control
unit) via CAN communication.
• Steering wheel rotation amount
• Steering wheel rotation angular velocity
• Steering wheel rotation direction

Yaw Rate/Side/Decel G sensor

INFOID:0000000006222565

Calculates the following information that affects the vehicle and transmits a signal to ABS actuator and electric
unit (control unit) via communication lines.
• Vehicle rotation angular velocity (yaw rate signal)
• Vehicle lateral acceleration (side G signal) / longitudinal acceleration (decel G signal)

Brake Fluid Level Switch

INFOID:0000000006222566

Detects the brake fluid level in reservoir tank and transmits converted electric signal from ABS actuator and
electric unit (control unit), when brake fluid level is the specified level or less.

Parking Brake Switch

INFOID:0000000006222567

Detects the operation status of parking brake switch and transmits converted electric signal from combination
meter to ABS actuator and electric unit (control unit).

VDC OFF Switch

INFOID:0000000006222568

• VDC OFF switch is integrated in SNOW MODE / TOW MODE / VDC OFF switch assembly (2WD models) or

4WD switch assembly (4WD models).

• The operation of the VDC OFF switch enables the arbitrary switching of the VDC function between stop sta-

tus and standby status. The status of the function is indicated by the VDC OFF indicator lamp. (ON: Non-
operational status, OFF: Standby status)

- VDC function

NOTE:
Brake limited slip differential (BLSD) control operates.

- TCS function
• VDC OFF indicator lamp turns OFF (standby status) when the engine is started again after it is stopped once

while VDC OFF indicator lamp is ON (non-operational status).

JPFIC0131GB

BRC-16

< SYSTEM DESCRIPTION >

[WITH VDC]

SYSTEM

SYSTEM

System Description

INFOID:0000000006222569

• The system switches fluid pressure of each brake caliper to increase, to hold or to decrease according to

signals from control unit in ABS actuator and electric unit (control unit). This control system is applied to
VDC function, TCS function, ABS function, EBD function, hill start assist function and brake limited slip dif-
ferential (BLSD) function

• Fail-safe function is available for each function and is activated by each function when system malfunction

occurs.

• The adoption of the 4WD switch assembly (4WD shift switch and VDC OFF switch) enables to change the

control characteristics of the VDC function, the TCS function and the brake limited slip differential (BLSD)
function into an optimal characteristics, based on a state of the 4WD shift switch. (Models with 4WD system)

SYSTEM DIAGRAM

NOTE:
Transfer control unit is applied to models with 4WD system.

INPUT SIGNAL AND OUTPUT SIGNAL

Major signal transmission between each unit via communication lines is shown in the following table.

JPFIC0182GB

Component

Signal description

Yaw rate/side/decel G sensor

Mainly transmits the following signals to ABS actuator and electric unit (control unit) via com-

munication line

*1

.

• Yaw rate signal
• Side G sensor signal
• Decel G sensor signal

ECM

Mainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN 
communication.
• Accelerator pedal position signal
• Engine speed signal
Mainly receives the following signals from ABS actuator and electric unit (control unit) via CAN 
communication.
• Target throttle position signal