2007 INFINITI QX56 sensor

SYSTEM DESCRIPTION
BRC-9
< SERVICE INFORMATION >[VDC/TCS/ABS]
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In case of an electrical malfunction with the ABS, the ABS warning lamp, VDC OFF indicator lamp and SLIP
indicator lamp will turn on. In case of an electrical malfunction with the EBD system, the BRAKE warning lamp,
ABS warning lamp, VDC OFF indicator lamp and SLIP indicator lamp will turn on.
The system will revert to one of the following conditions of the Fail-Safe function.
1. For ABS malfunction, only the EBD is operative and the condition of the vehicle is the same condition of
vehicles without ABS/TCS/VDC system.
2. For EBD malfunction, the EBD and ABS become inoperative, and the condition of the vehicle is the same
as the condition of vehicles without ABS/TCS/VDC or EBD system.
VDC/TCS SYSTEM
In case of TCS/VDC system malfunction, the VDC OFF indicator lamp and SLIP indicator lamp are turned on
and the condition of the vehicle is the same as the condition of vehicles without TCS/VDC system. In case of
an electrical malfunction with the TCS/VDC system, the ABS control continues to operate normally without
TCS/VDC control.
ACTIVE BOOSTER
The active brake booster consists of a vacuum booster, an active booster control group and a delta stroke
sensor. In case of brake booster system malfunction due to loss of vacuum, the delta stroke sensor will signal
the ABS actuator and electric unit (control unit) that a booster failure has occurred. The active booster then
applies supplemental force to the master cylinder relative to the amount of force exerted on the brake pedal.
Hydraulic Circuit DiagramINFOID:0000000003532774
WFIA0187E

TROUBLE DIAGNOSIS
BRC-11
< SERVICE INFORMATION >[VDC/TCS/ABS]
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TROUBLE DIAGNOSIS
How to Perform Trouble Diagnosis for Quick and Accurate RepairINFOID:0000000003532776
INTRODUCTION
The ABS/TCS/VDC system has an electronic control unit to control
major functions. The control unit accepts input signals from sensors
and controls actuator operation. It is also important to check for con-
ventional malfunctions such as air leaks in the booster or lines, lack
of brake fluid, or other malfunctions with the brake system.
It is much more difficult to diagnose a malfunction that occurs inter-
mittently rather than continuously. Most intermittent malfunctions are
caused by poor electrical connections or wiring. In this case, careful
checking of suspicious circuits may help prevent the replacement of
good parts.
A visual check only may not find the cause of the malfunction, so a
road test should be performed.
Before undertaking actual checks, take just a few minutes to talk with
a customer who approaches with an ABS/TCS/VDC complaint. The
customer is a very good source of information, especially for inter-
mittent malfunctions. Through the talks with the customer, find out
what symptoms are present and under what conditions they occur.
Start your diagnosis by looking for “conventional” malfunctions first.
This is one of the best ways to troubleshoot brake malfunctions on
an ABS/TCS/VDC equipped vehicle. Also check related Service Bul-
letins for information.
SEF233G
SEF234G

BRC-24
< SERVICE INFORMATION >[VDC/TCS/ABS]
TROUBLE DIAGNOSIS
Monitor item Display contentData monitor
Note: Error inspection
checklist
ConditionReference value in
normal operation
N POSI SIGPNP switch signal ON/
OFF conditionA/T shift position = N position ON
LAN-7
A/T shift position = other than N
positionsOFF
P POSI SIGPNP switch signal ON/
OFF conditionA/T shift position P position ON
LAN-7
A/T shift position = other than P
positionsOFF
GEAR A/T gear position1st gear 1
— 2nd gear 2
3rd gear 3
4th gear 4
5th gear 5
FR RH SENSOR
FR LH SENSOR
RR RH SENSOR
RR LH SENSORWheel speedVehicle stopped 0 [km/h (MPH)]
BRC-34, "
Wheel Sensor
System Inspection"Vehicle running (Note 1)Almost in accor-
dance with speed-
ometer display
(within ±10%)
ACCEL POS SIG Open/close condition
of throttle valve (linked
with accelerator pedal).Accelerator pedal not de-
pressed (ignition switch is ON)0%
LAN-7
Depress accelerator pedal (ig-
nition switch is ON)0 to 100%
ENGINE SPEED With engine runningWith engine stopped 0 rpm
BRC-35, "
Engine System
Inspection"Engine runningAlmost in accor-
dance with ta-
chometer display
STR ANGLE SIGSteering angle detect-
ed by steering angle
sensorStraight-ahead Approx. 0 deg
BRC-36, "
Steering Angle
Sensor System"Steering wheel turned –756 to 756 deg
YAW RATE SENYaw rate detected by
yaw rate sensorVehicle stopped Approx. 0 d/sBRC-37, "
Yaw Rate/Side/
Decel G Sensor System
Inspection"Vehicle running –100 to 100 d/s
SIDE G-SENSORTransverse G detected
by side G-sensorVehicle stopped
Approx. 0 m/s
2BRC-37, "Yaw Rate/Side/
Decel G Sensor System
Inspection"Vehicle running
–16.7 to 16.7 m/s2
BATTERY VOLTBattery voltage sup-
plied to ABS actuator
and electric unit (con-
trol unit)Ignition switch ON 10 to 16VBRC-41, "
ABS/TCS/VDC
Control Unit Power and
Ground Systems Inspec-
tion"
STOP LAMP SWStop lamp switch oper-
ationBrake pedal depressed ONBRC-40, "
Stop Lamp
Switch System Inspec-
tion"Brake pedal not depressed OFF
OFF SWVDC OFF switch
ON/OFF status VDC OFF switch ON
(When VDC OFF indicator
lamp is ON)ON
BRC-53, "
Component In-
spection"VDC OFF switch OFF
(When VDC OFF indicator
lamp is OFF)OFF
ABS WARN LAMPABS warning lamp ON
condition (Note 2)ABS warning lamp ON ON
—
ABS warning lamp OFF OFF

TROUBLE DIAGNOSIS
BRC-25
< SERVICE INFORMATION >[VDC/TCS/ABS]
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MOTOR RELAYOperation status of mo-
tor and motor relayIgnition switch ON or running
(ABS not activated)OFF
BRC-39, "
Actuator Motor,
Motor Relay, and Circuit
Inspection"Ignition switch ON or engine
running (ABS activated)ON
ACTUATOR RLYActuator relay opera-
tion statusVehicle stopped (Ignition
switch ON)OFF
BRC-39, "
Actuator Motor,
Motor Relay, and Circuit
Inspection"Vehicle stopped (Engine run-
ning)ON
OFF LAMPVDC OFF indicator
lamp status (Note 3) When VDC OFF indicator
lamp is ONON
LAN-7
When VDC OFF indicator
lamp is OFFOFF
SLIP LAMPSLIP indicator lamp
status (Note 4)When SLIP indicator lamp is
ONON
LAN-7
When SLIP indicator lamp is
OFFOFF
FR LH IN SOL
FR LH OUT SOL
FR RH IN SOL
FR RH OUT SOL
RR RH IN SOL
RR RH OUT SOL
RR LH IN SOL
RR LH OUT SOLSolenoid valve opera-
tionActuator (solenoid) is active
(“ACTIVE TEST” with CON-
SULT-II) or actuator relay is in-
active (in fail-safe mode).ON
BRC-38, "
Solenoid and
VDC Change-Over Valve
System Inspection"
When actuator (solenoid) is not
active and actuator relay is ac-
tive (ignition switch ON).OFF
CV1
CV2
SV1
SV2VDC switch-over valve
statusWhen actuator (switch-over
valve) is active (“ACTIVE
TEST” with CONSULT-II) or
actuator relay is inactive (when
in fail-safe mode).ON
When actuator (switch-over
valve) is not active and actua-
tor relay is active (ignition
switch ON).OFF
DECEL G-SENLongitudinal accelera-
tion detected by Decel
G-SensorVehicle stopped Approx. 0 GBRC-37, "
Yaw Rate/Side/
Decel G Sensor System
Inspection"Vehicle running -1.7 to 1.7 G
PRESS SENSORBrake fluid pressure
detected by pressure
sensorDo not step on the Brake pedal
(When ignition switch is ON)Approx. 0 bar
—
Step on the Brake pedal (When
ignition switch is ON)-40 to 300 bar
FLUID LEV SWON/OFF status of
brake fluid level switchWhen brake fluid level switch
ONON
DI-26
When brake fluid level switch
OFF OFF
VDC SIGNAL
TCS SIGNAL
ABS SIGNAL
EBD SIGNALSignal statusVDC active
TCS active
ABS active
EBD activeON
VDC system
TCS system
ABS system
EBD system VDC not active
TCS not active
ABS not active
EBD not activeOFF Monitor item Display contentData monitor
Note: Error inspection
checklist
ConditionReference value in
normal operation

TROUBLE DIAGNOSIS
BRC-27
< SERVICE INFORMATION >[VDC/TCS/ABS]
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3. Turn ignition switch ON.
4. Start engine and drive at approximately 30 km/h (19 MPH) or more for approximately 1 minute.
5. After stopping the vehicle, with the engine running, touch “START (NISSAN BASED VHCL)”, “ABS”,
“SELF-DIAG RESULTS” in order on the CONSULT-II screen.
CAUTION:
If “START (NISSAN BASED VHCL)” is touched immediately after starting the engine or turning on
the ignition switch, “ABS” might not be displayed in the SELECT SYSTEM screen. In this case,
repeat the operation from step 1.
6. The self-diagnostic results are displayed. (If necessary, the self-diagnostic results can be printed out by
touching “PRINT”.)
• When “NO DTC IS DETECTED” is displayed, check the ABS warning lamp, SLIP indicator lamp and
VDC OFF indicator lamp.
7. Conduct the appropriate inspection from the display item list, and repair or replace the malfunctioning
component.
8. Start engine and drive at approximately 30 km/h (19 MPH) or more for approximately 1 minute.
CAUTION:
• When a wheel sensor “short-circuit” is detected, if the vehicle is not driven at 30 km/h (19 MPH)
for at least 1 minute, the ABS warning lamp will not turn off even if the malfunction is repaired.
9. Turn ignition switch OFF to prepare for erasing the memory.
10. Start the engine and touch “START (NISSAN BASED VHCL)”, “ABS”, “SELF-DIAG RESULTS”, “ERASE”
in order on the CONSULT-II screen to erase the error memory.
If “ABS” is not indicated, go to GI-38, "
CONSULT-II Data Link Connector (DLC) Circuit".
CAUTION:
If the error memory is not erased, re-conduct the operation from step 5.
11. For the final inspection, drive at approximately 30 km/h (19 MPH) or more for approximately 1 minute and
confirm that the ABS warning lamp, SLIP indicator lamp, and VDC OFF indicator lamp are off.
Display Item List
Self-diagnostic item Malfunction detecting condition Check system
FR LH SENSOR 1
[C1104]Circuit of front LH wheel sensor is open, shorted or sensor power
voltage is unusual.
BRC-34, "
Wheel Sensor
System Inspection"
(Note 1) RR RH SENSOR 1
[C1101]Circuit of rear RH wheel sensor is open, shorted or sensor power
voltage is unusual.
FR RH SENSOR 1
[C1103]Circuit of front RH wheel sensor is open, shorted or sensor power
voltage is unusual.
RR LH SENSOR 1
[C1102]Circuit of rear LH wheel sensor is open, shorted or sensor power
voltage is unusual.
FR LH SENSOR 2
[C1108]ABS actuator and electric unit (control unit) cannot identify sensor
pulses, because of large gap between wheel sensor and sensor
rotor.
RR RH SENSOR 2
[C1105]ABS actuator and electric unit (control unit) cannot identify sensor
pulses, because of large gap between wheel sensor and sensor
rotor.
FR RH SENSOR 2
[C1107]ABS actuator and electric unit (control unit) cannot identify sensor
pulses, because of large gap between wheel sensor and sensor
rotor.
RR LH SENSOR 2
[C1106]ABS actuator and electric unit (control unit) cannot identify sensor
pulses, because of large gap between wheel sensor and sensor
rotor.
ABS SENSOR
[ C 111 5 ]Wheel sensor input is abnormal.
STOP LAMP SW
[ C 111 6 ]Stop lamp switch or circuit malfunction.BRC-40, "
Stop Lamp
Switch System Inspec-
tion"

BRC-28
< SERVICE INFORMATION >[VDC/TCS/ABS]
TROUBLE DIAGNOSIS
DECEL G SEN SET
[C1160]ABS decel sensor adjustment is incomplete.BRC-49, "Inspection for
Self-Diagnosis Result
"DECEL G SEN SET""
ST ANGL SEN SAFE
[C1163]When steering angle sensor is in safe mode.BRC-47, "Steering Angle
Sensor Safe Mode In-
spection"
ST ANG SEN CIRCUIT
[C1143]Neutral position of steering angle sensor is dislocated, or steering
angle sensor is malfunctioning.BRC-36, "Steering Angle
Sensor System"
YAW RATE SENSOR
[C1145]Yaw rate sensor has generated an error, or yaw rate sensor signal
line is open or shorted.BRC-37, "Yaw Rate/
Side/Decel G Sensor
System Inspection"
FR LH IN ABS SOL
[C1120]Circuit of front LH IN ABS solenoid is open or shorted, or control
line is open or shorted to power supply or ground.
BRC-38, "
Solenoid and
VDC Change-Over Valve
System Inspection"
FR LH OUT ABS SOL
[C1121]Circuit of front LH OUT ABS solenoid is open or shorted, or control
line is open or shorted to power supply or ground.
RR RH IN ABS SOL
[C1126]Circuit of rear RH IN ABS solenoid is open or shorted, or control
line is open or shorted to power supply or ground.
RR RH OUT ABS SOL
[C1127]Circuit of rear RH OUT ABS solenoid is open or shorted, or control
line is open or shorted to power supply or ground.
FR RH IN ABS SOL
[C1122]Circuit of front RH IN ABS solenoid is open or shorted, or control
line is open or shorted to power supply or ground.
FR RH OUT ABS SOL
[C1123]Circuit of front RH OUT ABS solenoid is open or shorted, or con-
trol line is open or shorted to power supply or ground.
RR LH IN ABS SOL
[C1124]Circuit of rear LH IN ABS solenoid is open or shorted, or control
line is open or shorted to power supply or ground.
RR LH OUT ABS SOL
[C1125] Circuit of rear LH OUT ABS solenoid is open or shorted, or control
line is open or shorted to power supply or ground.
CV1
[C1164]Front side VDC switch-over solenoid valve (cut valve) is open or
shorted, or control line is open or shorted to power supply or
ground.
CV2
[C1165]Rear side VDC switch-over solenoid valve (cut valve) is open or
shorted, or control line is open or shorted to power supply or
ground.
SV1
[C1166]Front side VDC switch-over solenoid valve (suction valve) is open
or shorted, or control line is open or shorted to power supply or
ground.
SV2
[C1167]Rear side VDC switch-over solenoid valve (suction valve) is open
or shorted, or control line is open or shorted to power supply or
ground.
PUMP MOTOR
[ C 1111 ]During actuator motor operation with ON, when actuator motor
turns OFF or when control line for actuator motor relay is open.BRC-39, "
Actuator Mo-
tor, Motor Relay, and Cir-
cuit Inspection"During actuator motor operation with OFF, when actuator motor
turns ON or when control line for relay is shorted to ground.
BATTERY VOLTAGE
[ABNORMAL]
[C1109]ABS actuator and electric unit (control unit) power voltage is too
low.BRC-41, "
ABS/TCS/VDC
Control Unit Power and
Ground Systems Inspec-
tion"
ST ANG SEN SIGNAL
[C1144]Neutral position correction of steering angle sensor is not finished.BRC-48, "Inspection for
Self-Diagnosis Result
"ST ANG SEN SIGNAL""
ST ANG SEN COM CIR
[C1156]CAN communication line or steering angle sensor has generated
an error.BRC-36, "Steering Angle
Sensor System"
G-SENSOR
[ C 111 3 ]Longitudinal G-sensor is malfunctioning, or signal line of longitu-
dinal G-sensor is open or shorted.BRC-37, "Yaw Rate/
Side/Decel G Sensor
System Inspection"
Self-diagnostic item Malfunction detecting condition Check system

TROUBLE DIAGNOSIS
BRC-29
< SERVICE INFORMATION >[VDC/TCS/ABS]
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Note 1: If wheel sensor 2 for each wheel is indicated, check ABS actuator and electric unit (control unit) power supply voltage in addition
to wheel sensor circuit check.
Note 2: If multiple malfunctions are detected including CAN communication line [U1000], perform diagnosis for CAN communication line
first.
DATA MONITOR
Display Item List
CONTROLLER FAILURE
[ C 111 0 ]Internal malfunction of ABS actuator and electric unit (control
unit).BRC-35, "ABS/TCS/VDC
Control Unit Inspection"
CAN COMM CIRCUIT
[U1000]• CAN communication line is open or shorted.
• ABS actuator and electric unit (control unit) internal malfunction
• Battery voltage for ECM is suddenly interrupted for approxi-
mately 0.5 second or more.LAN-7 (Note 2)
SIDE G-SEN CIRCUIT
[C1146]Lateral G-sensor is malfunctioning, or signal line of lateral G-sen-
sor is open or shorted.BRC-37, "
Yaw Rate/
Side/Decel G Sensor
System Inspection"
BR FLUID LEVEL LOW
[C1155]Brake fluid level drops or circuit between ABS actuator and elec-
tric unit (control unit) and brake fluid level switch is open or
shorted.BRC-42, "Brake Fluid
Level Switch System In-
spection"
ENGINE SIGNAL 1
[C1130]Based on the signal from ECM, ABS actuator and electric unit
(control unit) judges that engine fuel cut system is malfunctioning.
BRC-35, "
Engine System
Inspection"
ENGINE SIGNAL 2
[C1131]Based on the signal from ECM, ABS actuator and electric unit
(control unit) judges that engine fuel cut system is malfunctioning.
ENGINE SIGNAL 3
[C1132]Based on the signal from ECM, ABS actuator and electric unit
(control unit) judges that engine fuel cut system is malfunctioning.
ENGINE SIGNAL 4
[C1133]Based on the signal from ECM, ABS actuator and electric unit
(control unit) judges that engine fuel cut system is malfunctioning.
ENGINE SIGNAL 6
[C1136]Based on the signal from ECM, ABS actuator and electric unit
(control unit) judges that engine fuel cut system is malfunctioning.
ACTUATOR RLY
[C1140]ABS actuator relay or circuit malfunction.BRC-39, "
Actuator Mo-
tor, Motor Relay, and Cir-
cuit Inspection"
PRESS SEN CIRCUIT
[C1142]ABS pressure sensor circuit malfunction.BRC-45, "Pressure Sen-
sor System Inspection"
VARIANT CODING
[C1170]V coding is not malfunctioning.BRC-35, "ABS/TCS/VDC
Control Unit Inspection"
ABS ACTIVE BOOSTER SV NG
[C1178]Active booster solenoid is malfunctioning, or signal line of active
booster servo is open or shorted.BRC-43, "Active Booster
System Inspection"
ABS DELTA S SEN NG
[C1179]Delta stroke sensor malfunctioning, or signal line of delta stroke
sensor is open or shorted.BRC-44, "Delta Stroke
Sensor System Inspec-
tion"
ABS ACTIVE BOOSTER RE-
SPONSE NG
[C1181]Active booster response is malfunctioning, or signal line of active
booster response is open or shorted.BRC-43, "Active Booster
System Inspection"
ABS BRAKE RELEASE SW NG
[C1184]Brake release switch is malfunctioning, or signal line of brake re-
lease switch is open or shorted.BRC-43, "Active Booster
System Inspection"
ABS ACC CU INTERNAL NG
[C1185]ICC control unit internal malfunction.BRC-48, "ICC System In-
spection"
ABS BRAKE BOOSTER DEFECT
[C1189]Brake booster is defective or malfunctioning.BRC-43, "Active Booster
System Inspection"
Self-diagnostic item Malfunction detecting condition Check system

BRC-30
< SERVICE INFORMATION >[VDC/TCS/ABS]
TROUBLE DIAGNOSIS
Item
(Unit)Data monitor item selection
Remarks
ECU INPUT
SIGNALSMAIN
SIGNALSSELECTION
FROM MENU
GEAR×××Gear position judged by PNP switch
signal is displayed.
FR RH SENSOR
(km/h, MPH)×××Wheel speed calculated by front RH
wheel sensor signal is displayed.
FR LH SENSOR
(km/h, MPH)×××Wheel speed calculated by front LH
wheel sensor signal is displayed.
RR RH SENSOR
(km/h, MPH)×××Wheel speed calculated by rear RH
wheel sensor signal is displayed.
RR LH SENSOR
(km/h, MPH)×××Wheel speed calculated by rear LH
wheel sensor signal is displayed.
BATTERY VOLT
(V)×××Voltage supplied to ABS actuator
and electric unit (control unit) is dis-
played.
N POSI SIG – –×Shift position judged by PNP switch
signal.
P POSI SIG – –×Shift position judged by PNP switch
signal.
ACCEL POS SIG
(%)×–×Throttle valve open/close status
judged by CAN communication sig-
nal is displayed.
ENGINE SPEED
(rpm)×××Engine speed judged by CAN com-
munication signal is displayed.
STR ANGLE SIG
(deg)×–×Steering angle detected by steering
angle sensor is displayed.
YAW RATE SEN
(d/s)×××Yaw rate detected by yaw rate sen-
sor is displayed.
DECEL G-SEN
(d/s)×××Longitudinal acceleration detected
by decel G-sensor is displayed.
SIDE G-SENSOR
(m/s
2)×– ×Transverse acceleration detected
by side G-sensor is displayed.
STOP LAMP SW
(ON/OFF)×××Stop lamp switch (ON/OFF) status
is displayed.
OFF SW
(ON/OFF) ×× ×VDC OFF switch (ON/OFF) status
is displayed.
ABS WARN LAMP
(ON/OFF)–××ABS warning lamp (ON/OFF) status
is displayed.
SLIP LAMP
(ON/OFF)–××SLIP indicator lamp (ON/OFF) sta-
tus is displayed.
FR LH IN SOL
(ON/OFF)–××Front LH IN ABS solenoid (ON/
OFF) status is displayed.
FR LH OUT SOL
(ON/OFF)–××Front LH OUT ABS solenoid (ON/
OFF) status is displayed.
RR RH IN SOL
(ON/OFF)–××Rear RH IN ABS solenoid (ON/
OFF) status is displayed.
RR RH OUT SOL
(ON/OFF) –××Rear RH OUT ABS solenoid (ON/
OFF) status is displayed.
FR RH IN SOL
(ON/OFF)–××Front RH IN ABS solenoid (ON/
OFF) status is displayed.
FR RH OUT SOL
(ON/OFF)–××Front RH OUT ABS solenoid (ON/
OFF) status is displayed.