2011 INFINITI QX56 sensor

BRC-30
< SYSTEM DESCRIPTION >[WITH VDC]
SYSTEM
Major signal transmission between each unit via communication lines is shown in the following table.
*1: Communication line between yaw rate/side/decal G s
ensor and ABS actuator and electric unit (control unit)
*2: Models with 4WD system
OPERATION CHARACTERISTICS
VDC Function That Prevents Oversteer Tendency
 During a cornering, brake force (brake fluid pressure) is applied on front wheel and rear wheel on the outer side of turn. Moment directing towards the outer side of turn is generated. Oversteer is prevented.
 Changing driving lane on a slippery road, when oversteer tendency is judged large, engine output is con- trolled as well as brake force (brake fluid pr essure) of 4 wheels. Oversteer tendency decreases.
VDC Function That Prevents Understeer Tendency
Component Signal description
Yaw rate/side/decel G sensor Mainly transmits the following si
gnals 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 si
gnals 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
TCM Mainly transmits the following si
gnals to ABS actuator and electric unit (control unit) via CAN
communication.
 Shift position signal
Transfer control unit
*2Mainly transmits the following si gnals to ABS actuator and electric unit (control unit) via CAN
communication.
 Current 4WD mode signal
Steering angle sensor Mainly transmits the following si
gnals to ABS actuator and electric unit (control unit) via CAN
communication.
 Steering angle sensor signal
Combination meter Mainly receives
the following signals from ABS actuator and electric unit (control unit) via CAN
communication.
 VDC warning lamp signal
 VDC OFF indicator lamp
JPFIC0135GB
JPFIC0136GB
Revision: 2010 May2011 QX56

SYSTEMBRC-31
< SYSTEM DESCRIPTION > [WITH VDC]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
 During a cornering, brake force (brake fluid pressu re) is applied on front wheel and rear wheel on the inner
side of turn. Moment directing towards the inner side of turn is generated. Understeer is prevented.
 Applying braking during a cornering on a slippery road, when understeer tendency is judged large, engine
output is controlled as well as brake force (brake fluid pressure) of four wheels. Understeer tendency
decreases.
TCS FUNCTION
TCS FUNCTION : System DescriptionINFOID:0000000006222573
 Wheel spin status of drive wheel is detected by wheel sensor of 4
wheels. Engine output and transmission shift status is controlled
so that slip rate of drive wheels is in appropriate level. When wheel
spin occurs on drive wheel, ABS ac tuator and electric unit (control
unit) perform brake force control of LH and RH drive wheels (apply
brake force by increasing brake fluid pressure of drive wheel) and
decrease engine torque by engine torque control. Wheel spin
amount decreases. Engine torque is controlled to appropriate
level.
 TCS function can be switched to non-operational status (OFF) by
operating VDC OFF switch. In this case, VDC OFF indicator lamp
turns ON.
 TCS function is not operate when 4WD mode is “4L”. (Models with
4WD system)
 VDC warning lamp blinking while TCS function is in operation and indicates to the driver that the function is in operation.
 Slight vibrations are felt on the brake pedal and the operation noises occur, when TCS function operates. This is not a malfunc-
tion because it is caused by TCS function that is normally oper-
ated.
 CONSULT-III can be used to diagnose the system diagnosis.
 Fail-safe function is adopted. W hen a malfunction occurs in TCS
function, the control is suspended for VDC function, TCS function,
hill start assist function and brake limited slip differential (BLSD)
function. The vehicle status becomes the same as models without VDC function, TCS function, hill start
assist function and brake limited slip differential (B LSD) function. However, ABS function and EBD function
are operated normally. Refer to BRC-25, "
Fail-safe".
SYSTEM DIAGRAM
NOTE:
JPFIC0137GB
JPFIC0138GB
JPFIC0139GB
Revision: 2010 May2011 QX56

BRC-32
< SYSTEM DESCRIPTION >[WITH VDC]
SYSTEM
Transfer control unit is appli
ed 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.
*1: Communication line between yaw rate/side/decal G s ensor and ABS actuator and electric unit (control unit)
*2: Models with 4WD system
ABS FUNCTION
JPFIC0183GB
Component Signal description
Yaw rate/side/decel G sensor Mainly transmits the following si
gnals 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 si
gnals 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
TCM Mainly transmits the following si
gnals to ABS actuator and electric unit (control unit) via CAN
communication.
 Shift position signal
Transfer control unit
*2Mainly transmits the following si gnals to ABS actuator and electric unit (control unit) via CAN
communication.
 Current 4WD mode signal
Steering angle sensor Mainly transmits the following si
gnals to ABS actuator and electric unit (control unit) via CAN
communication.
 Steering angle sensor signal
Combination meter Mainly receives
the following signals from ABS actuator and electric unit (control unit) via CAN
communication.
 VDC warning lamp signal
 VDC OFF indicator lamp
Revision: 2010 May2011 QX56

BRC-34
< SYSTEM DESCRIPTION >[WITH VDC]
SYSTEM
Transfer control unit is appli
ed 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.
*1: Communication line between yaw rate/side/decal G s ensor and ABS actuator and electric unit (control unit)
*2: Models with 4WD system
EBD FUNCTION
EBD FUNCTION : System DescriptionINFOID:0000000006222575
 By preventing rear wheel slip increase through rear wheel brake force (brake fluid pressure) control that is
electronically controlled when slight skip on front and r ear wheels are detected during braking, stability dur-
ing braking is improved.
JPFIC0184GB
Component Signal description
Yaw rate/side/decel G sensor Mainly transmits the following si
gnals to ABS actuator and electric unit (control unit) via com-
munication line
*1.
 Yaw rate signal
 Side G sensor signal
 Decel G sensor signal
Transfer control unit
*2Mainly transmits the following si gnals to ABS actuator and electric unit (control unit) via CAN
communication.
 Current 4WD mode signal
Combination meter Mainly receives
the following signals from ABS actuator and electric unit (control unit) via CAN
communication.
 ABS warning lamp signal
Revision: 2010 May2011 QX56

SYSTEMBRC-35
< SYSTEM DESCRIPTION > [WITH VDC]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
 EBD function is expanded and developed from conventi onal ABS function and corrects rear wheel brake
force to appropriate level by electronic control according to load weight (number of passengers).
 During braking, control unit portion compares slight slip on front and rear wheels by wheel speed sensor signal, transmits drive sig-
nal to actuator portion when rear wheel slip exceeds front wheel
slip for the specified value or more, and controls rear wheel brake
force (brake fluid pressure) so t hat increase of rear wheel slip is
prevented and slips on front wheel and rear wheel are nearly
equalized. ABS control is applied when slip on each wheel
increases and wheel speed is the threshold value of ABS control or
less.
 CONSULT-III can be used to diagnose the system diagnosis.
 Fail-safe function is adopted. When a malfunction occurs in EBD function, the control is suspended for VDC function, TCS function,
ABS function, EBD function, hill start assist function and brake lim-
ited slip differential (BLSD) func tion. The vehicle status becomes
the same as models without VDC function, TCS function, ABS
function, EBD function, hill start assist function and brake limited
slip differential (BLSD) function. Refer to BRC-25, "
Fail-safe".
JPFIC0142GB
JPFIC0143GB
Revision: 2010 May2011 QX56

SYSTEMBRC-37
< SYSTEM DESCRIPTION > [WITH VDC]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
SYSTEM DIAGRAM
INPUT SIGNAL AND OUTPUT SIGNAL
Major signal transmission between each unit via communication lines is shown in the following table.
*: Communication line between yaw rate/side/decal G s ensor and ABS actuator and electric unit (control unit)
BRAKE LIMITED SLIP DIFFERENTIAL (BLSD) FUNCTION
BRAKE LIMITED SLIP DIFFERENTIAL (BLSD) FUNCTION : System Description
INFOID:0000000006222577
 LH and RH driving wheel spin is always monitored. If necessary, appropriate brake force is independently
applied to LH or RH driving wheel so that one-sided wheel spin is avoided and traction is maintained. Mainly
starting ability is improved.
JPFIC0145GB
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 *.
 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
TCM Mainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN
communication.
 Shift position signal
Combination meter Mainly receives the following signals from ABS actuator and electric unit (control unit) via CAN
communication.
 VDC warning lamp signal
 VDC OFF indicator lamp signal
Revision: 2010 May2011 QX56

BRC-38
< SYSTEM DESCRIPTION >[WITH VDC]
SYSTEM
 Brake limited slip differential (BLSD) function operates
while VDC function is in non-operational status (OFF)
by VDC OFF switch.
 VDC warning lamp blinking while brake limited slip di fferential (BLSD) function is in operation and indicates
to the driver that the function is in operation.
 Slight vibrations are felt on the brake pedal and the operation noises occur, when brake limited slip differen-
tial (BLSD) function operates. This is not a malfunction because it is caused by brake limited slip differential
(BLSD) function that is normally operated.
 Fail-safe function is adopted. When a malfunction occurs in brake limited slip differential (BLSD) function,
the control is suspended for VDC function, TCS function, hi ll start assist function and brake limited slip differ-
ential (BLSD) function. The vehicle status becomes the same as models without VDC function, TCS func-
tion, hill start assist function and brake limited slip di fferential (BLSD) function. However, ABS function and
EBD function are operated normally. Refer to BRC-25, "
Fail-safe".
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.
JPFIC0183GB
Component Signal description
Yaw rate/side/decel G sensor Mainly transmits the following si
gnals 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 si
gnals 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
TCM Mainly transmits the following si
gnals to ABS actuator and electric unit (control unit) via CAN
communication.
 Shift position signal
Revision: 2010 May2011 QX56

SYSTEMBRC-39
< SYSTEM DESCRIPTION > [WITH VDC]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
*1: Communication line between yaw rate/side/decal G s ensor and ABS actuator and electric unit (control unit)
*2: Models with 4WD system
Transfer control unit*2Mainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN
communication.
 Current 4WD mode signal
Steering angle sensor Mainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN
communication.
 Steering angle sensor signal
Combination meter Mainly receives the following signals from ABS actuator and electric unit (control unit) via CAN
communication.
 VDC warning lamp signal
 VDC OFF indicator lamp
Component Signal description
Revision: 2010 May2011 QX56