INFINITI QX56 2010 Factory Service Manual

ABS
BRC-19
< FUNCTION DIAGNOSIS > [VDC/TCS/ABS]
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Component DescriptionINFOID:0000000005147957
7. VDC OFF switch M253 8. Active booster E499. Delta stroke sensor E114
10. Brake fluid level switch E21 11. Front pressure sensor E31 12. Rear pressure sensor E32
Component parts Reference
ABS actuator and electric unit (control unit)Pump
BRC-37, "
Description"Motor
Actuator relayBRC-55, "
Description"
Solenoid valveBRC-47, "Description"
Wheel sensor BRC-28, "Description"
ABS warning lampBRC-82, "Description"
Brake warning lampBRC-83, "Description"
Revision: April 20092010 QX56

BRC-20
< FUNCTION DIAGNOSIS >[VDC/TCS/ABS]
EBD
EBD
System DiagramINFOID:0000000005147958
System DescriptionINFOID:0000000005147959
• Electric Brake force Distribution is a following functi
on. ABS actuator and electric unit (control unit) detects
subtle slippages between the front and rear wheels during braking. Then it electronically controls the rear
braking force (brake fluid pressure) to reduce rear wheel slippage. Accordingly, it improves vehicle stability.
• Electrical system diagnosis by CONSULT-III is available.
AWFIA0014GB
Revision: April 20092010 QX56

EBD
BRC-21
< FUNCTION DIAGNOSIS > [VDC/TCS/ABS]
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Component Parts LocationINFOID:0000000005206967
1. Front wheel sensor LH E18 Front wheel sensor RH E117 2. ABS actuator and electric unit (con-
trol unit) E125 3. Combination meter M23, M24
4. Rear wheel sensor LH C11 Rear wheel sensor RH C10 5. Yaw rate/side/decel G sensor M108 6. Steering angle sensor M17
AWFIA0572GB
Revision: April 20092010 QX56

BRC-22
< FUNCTION DIAGNOSIS >[VDC/TCS/ABS]
EBD
Component Description
INFOID:0000000005206968
7. VDC OFF switch M253 8. Active booster E499. Delta stroke sensor E114
10. Brake fluid level switch E21 11. Front pressure sensor E31 12. Rear pressure sensor E32
Component parts Reference
ABS actuator and electric unit (control unit) Pump
BRC-37, "
Description"Motor
Actuator relayBRC-55, "
Description"
Solenoid valveBRC-47, "Description"
Wheel sensor BRC-28, "Description"
ABS warning lampBRC-82, "Description"
Brake warning lampBRC-83, "Description"
Revision: April 20092010 QX56

DIAGNOSIS SYSTEM [ABS ACTUATOR AND ELECTRIC UNIT (CONTROL
UNIT)]
BRC-23
< FUNCTION DIAGNOSIS > [VDC/TCS/ABS]
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DIAGNOSIS SYSTEM [ABS ACTUATOR AND ELECTRIC UNIT (CONTROL
UNIT)]
CONSULT-III Function (ABS)INFOID:0000000005147962
FUNCTION
CONSULT-III can display each diagnostic item using the diagnostic test modes shown following.
SELF DIAGNOSTIC RESULT MODE
Operation Procedure
1. Before performing the self-diagnosis, start engine and drive vehicle at 30 km/h (19 MPH) or more for
approximately 1 minute.
How to Erase Self-diagnosis Results
1. After erasing DTC memory, start engine and drive vehicle at 30 km/h (19 MPH) or more for approximately 1 minute as the final inspection, and make sure t hat the ABS warning lamp, VDC OFF indicator lamp,
SLIP indicator lamp and brake warning lamp turn OFF.
CAUTION:
If memory cannot be erased, perform applicable diagnosis.
NOTE:
• When the wheel sensor malfunctions, after inspecting the wheel sensor system, the ABS warning lamp,
VDC OFF indicator lamp, SLIP indicator lamp and brake warning lamp will not turn OFF even when the
system is normal unless the vehicle is driving at approximately 30 km/h (19 MPH) or more for approxi-
mately 1 minute.
• Brake warning lamp will turn ON in case of parking brake operation (when switch is ON) or of brake fluid level switch operation (when brake fluid is insufficient).
• VDC OFF switch should not stay “ON” position.
Display Item List
Refer to BRC-100, "DTC No. Index".
DATA MONITOR MODE
Display Item List
Diagnostic test mode Function
Work support This mode enables a technician to adjust some devices faster and more accurately by following
the indications on CONSULT-III.
Data Monitor Input/Output data in the ABS actuator and electric uni t (control unit) can be read.
Active Test Diagnostic test mode is which CONSULT-III driv
es some actuators apart from the ABS actuator
and electric unit (control unit) and also shifts some parameters in a specified range.
Self Diagnostic Result Self-diagnostic results can be read and erased quickly.
CAN diag support monitor The results of transmit/receive diagnosis of CAN communication can be read.
ECU Identification ABS actuator and electric unit (control unit) part number can be read.
Item
(Unit) Data monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELECTION
FROM MENU
FR LH SENSOR
(km/h, mph) ×× × Wheel speed (km/h, mph) calculated by front LH
wheel sensor signal is displayed.
FR RH SENSOR
(km/h, mph) ×× ×
Wheel speed (km/h, mph) calculated by front RH
wheel sensor signal is displayed.
RR LH SENSOR
(km/h, mph) ×× × Wheel speed (km/h, mph) calculated by rear LH
wheel sensor signal is displayed.
RR RH SENSOR
(km/h, mph) ×× × Wheel speed (km/h, mph) calculated by rear RH
wheel sensor signal is displayed.
Revision: April 20092010 QX56

BRC-24
< FUNCTION DIAGNOSIS >[VDC/TCS/ABS]
DIAGNOSIS SYSTEM [
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL
UNIT)]
DECEL G-SEN
(G) ×× × Longitudinal acceleration (G) detected by decel G-
sensor is displayed.
FR RH IN SOL
(On/Off) –
×× Front RH IN ABS solenoid (On/Off) status is dis-
played.
FR RH OUT SOL
(On/Off) –
×× Front RH OUT ABS solenoid (On/Off) status is dis-
played.
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 dis-
played.
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 dis-
played.
RR LH IN SOL
(On/Off) –
×× Rear LH IN ABS solenoid (On/ Off) status is displayed.
RR LH OUT SOL
(On/Off) –
×× Rear LH OUT ABS solenoid (On/Off) status is dis-
played.
EBD WARN LAMP
(On/Off) ––
×Brake warning lamp (On/Off) status is displayed.
STOP LAMP SW
(On/Off) ×× ×
Stop lamp switch (On/Off) status is displayed.
MOTOR RELAY
(On/Off) –
×× ABS motor relay signal (On/Of f) status is displayed.
ACTUATOR RLY
(On/Off) –
×× ABS actuator relay signal (On/ Off) status is displayed.
ABS WARN LAMP
(On/Off) –
×× ABS warning lamp (On/Off) status is displayed.
OFF LAMP
(On/Off) –
×× VDC OFF Lamp (On/Off) status is displayed.
OFF SW
(On/Off) ×× ×
VDC OFF switch (On/Off) status is displayed.
SLIP LAMP
(On/Off) –
×× SLIP indicator lamp (On/Off) status is displayed.
BATTERY VOLT
(V) ×× ×
Voltage (V) supplied to ABS actuator and electric unit
(control unit) is displayed.
GEAR
(1 , 2

, 3, 4, 5) ×× × Gear position (1, 2, 3, 4, 5) judged by transmission
range switch signal is displayed.
SLCT LVR POSI
(P, N, D) ×× × Shift position (P, N, D) judged by transmission range
switch signal.
ENGINE SPEED
(rpm) ×× ×
Engine speed (rpm) judged by CAN communication
signal is displayed.
YAW R AT E S E N
(d/s) ×× × Yaw rate (d/s) detected by yaw rate sensor is dis-
played.
R POSI SIG
(On/Off) ––
×Reverse shift position (On/Off) judged by PNP switch
signal.
4WD FAIL REQ
(On/Off) ––
×Transfer control unit fail-safe mode (On/Off) is dis-
played.
N POSI SIG
(On/Off) ––
×Shift position judged by transmission range switch
signal.
Item
(Unit) Data monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELECTION
FROM MENU
Revision: April 20092010 QX56

DIAGNOSIS SYSTEM [ABS ACTUATOR AND ELECTRIC UNIT (CONTROL
UNIT)]
BRC-25
< FUNCTION DIAGNOSIS > [VDC/TCS/ABS]
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P POSI SIG
(On/Off) ––
×Shift position judged by transmission range switch
signal.
CV1
(On/Off) ––
×Front side switch-over solenoid valve (cut valve) (On/
Off) status is displayed.
CV2
(On/Off) ––
×Rear side switch-over solenoid valve (cut-valve) (On/
Off) status is displayed.
SV1
(On/Off) ––
×Front side switch-over solenoid valve (suction valve)
(On/Off) status is displayed.
SV2
(On/Off) ––
×Rear side switch-over solenoid valve (suction valve)
(On/Off) status is displayed.
2WD/4WD
(2WD/4WD) ––
×It recognizes on software whether it is 2WD and
whether it is in 4WD state.
ACCEL POS SIG
(%) ×
– ×Throttle valve open/close status judged by CAN com-
munication signal is displayed.
SIDE G-SENSOR
(m/s
2) ×
– ×Transverse acceleration detected by side G-sensor is
displayed.
STR ANGLE SIG
(deg) ×
– ×Steering angle detected by steering angle sensor is
displayed.
BST OPER SIG
(On/Off) ––
×Active booster operation (On/Off) status is displayed.
PRESS SENSOR
(bar) ×
– ×Brake pressure detected by pressure sensor is dis-
played.
EBD SIGNAL
(On/Off) ––
×EBD operation (On/Off) status is displayed.
ABS SIGNAL
(On/Off) ––
×ABS operation (On/Off) status is displayed.
TCS SIGNAL
(On/Off) ––
×TCS operation (On/Off) status is displayed.
VDC SIGNAL
(On/Off) ––
×VDC operation (On/Off) status is displayed.
EBD FAIL SIG
(On/Off) ––
×EBD fail signal (On/Off) status is displayed.
ABS FAIL SIG
(On/Off) ––
×ABS fail signal (On/Off) status is displayed.
TCS FAIL SIG
(On/Off) ––
×TCS fail signal (On/Off) status is displayed.
VDC FAIL SIG
(On/Off) ––
×VDC fail signal (On/Off) status is displayed.
CRANKING SIG
(On/Off) ––
×The input state of the key SW START position signal
is displayed.
FLUID LEV SW
(On/Off) ×
– ×Brake fluid level switch (On/Off) status is displayed.
PRESS SEN2
(bar) ––
×Brake pressure detected by pressure sensor is dis-
played.
DELTA S SEN
(mm) ––
×The amount of stroke sensor movements in the active
booster detected by DELTA S SEN is displayed.
RELEASE SW NO
(On/Off) ––
×Release switch signal (On/Off) status is displayed.
“On” indicates that the brake pedal is depressed. “Off”
indicates that the brake pedal is released.
Item
(Unit) Data monitor item selection
Remarks
ECU INPUT
SIGNALS MAI
N
SIGNALS SELECT
ION
FROM MENU
Revision: April 20092010 QX56

BRC-26
< FUNCTION DIAGNOSIS >[VDC/TCS/ABS]
DIAGNOSIS SYSTEM [
ABS ACTUATOR AND ELECTRIC UNIT (CONTROL
UNIT)]
×: Applicable
–: Not applicable
ACTIVE TEST MODE
CAUTION:
• Do not perform active test while driving vehicle.
• Make sure to completely bleed air from brake system.
• The active test cannot be performed with the ABS warning lamp, VDC OFF indicator lamp, SLIP indi-
cator lamp or brake warning lamp on.
• ABS warning lamp, VDC OFF indicator lamp, SLIP indicator lamp and brake warning lamp are on
during active test.
NOTE:
• When active test is performed while depressing the pedal, the pedal depression amount will change. This is
normal. (Only solenoid valve and ABS motor.)
• “TEST IS STOPPED” is displayed 10 seconds after operation start.
• After “TEST IS STOPPED” is display ed, to perform test again, touch BACK.
Test Item
SOLENOID VALVE• When performing an active test of the ABS function, select the “MAIN SIGNAL S” for each test item.
• For ABS solenoid valve, touch “Up”, “Keep”, and “D own” on the display screen. For ABS solenoid valve
(ACT), touch “Up”, “ACT UP”, “ACT KEEP” and confirm that solenoid valves operate as shown in the table
below.
RELEASE SW NC
(On/Off) ––
×Release switch signal (On/Off) status is displayed.
“Off” indicates that the brake pedal is depressed. “On”
indicates that the brake pedal is released.
OHB FAIL
(On/Off) ––
×OHB fail status is displayed.
HBA FAIL
(On/Off) ––
×HBA fail status is displayed.
OHB SIG
(On/Off) ––
×OHB operation (On/Off) status is displayed.
HBA SIG
(On/Off) ––
×HBA operation (On/Off) status is displayed.
STP OFF RLY
(On/Off) ––
×Stop lamp relay signal (On/Off) status is displayed.
Item
(Unit) Data monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELECTION
FROM MENU
Operation ABS solenoid valve ABS solenoid valve (ACT)
Up Keep Down Up ACT UP ACT KEEP
FR RH SOL FR RH IN SOL Off On On — —
—
FR RH OUT SOL Off Off On* — — —
FR LH SOL FR LH IN SOL Off On On — —
—
FR LH OUT SOL Off Off On* — — —
RR RH SOL RR RH IN SOL Off On On — —
—
RR RH OUT SOL Off Off On* — — —
RR LH SOL RR LH IN SOL Off On On — —
—
RR LH OUT SOL Off Off On* — — —
FR RH ABS SOLENOID (ACT) FR RH IN SOL — — — Off Off Off
FR RH OUT SOL — — — Off Off Off
CV1 ———OffOnOn
SV1
— — — Off On* Off
Revision: April 20092010 QX56

DIAGNOSIS SYSTEM [ABS ACTUATOR AND ELECTRIC UNIT (CONTROL
UNIT)]
BRC-27
< FUNCTION DIAGNOSIS > [VDC/TCS/ABS]
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O P*: On for 1 to 2 seconds after the touch, and then Off
ABS MOTOR
• Touch “On” and “Off” on screen. Make sure motor relay and actuator relay operates as shown in table below.
BOOSTER DRIVE• Touch “Up” and “Down” on the screen. Check that booster drive operates as shown in table below.
CAUTION:
Perform active test subject to the conditions below.
• Do not operate brake pedal during active test.
• Make sure the engine revolution is over 500 rpm.
• Make sure the vehicle is not moving.
FR LH ABS SOLENOID (ACT) FR LH IN SOL — — — Off Off Off
FR LH OUT SOL — — — Off Off Off
CV1 ———OffOnOn
SV1
— — — Off On* Off
RR RH ABS SOLENOID (ACT) RR RH IN SOL — — — Off Off Off
RR RH OUT SOL — — — Off Off Off
CV2 ———OffOnOn
SV2
— — — Off On* Off
RR LH ABS SOLENOID (ACT) RR LH IN SOL — — — Off Off Off
RR LH OUT SOL — — — Off Off Off
CV2 ———OffOnOn
SV2
— — — Off On* Off
Operation
ABS solenoid va
lve ABS solenoid valve (ACT)
Up Keep Down Up ACT UP ACT KEEP
Operation OnOff
MOTOR RELAY OnOff
ACTUATOR RLY OnOn
Operation UpDown
BST OPER SIG OnOff
PRESS SENSOR 50 ± 5 bar 0 bar
PRESS SEN 2 50 ± 5 bar 0 bar
STOP LAMP SW OnOff
STP OFF RLY OffOff
Revision: April 20092010 QX56

BRC-28
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1101, C1102, C1103,
C1104 WHEEL SENSOR-1
COMPONENT DIAGNOSIS
C1101, C1102, C1103, C1104 WHEEL SENSOR-1
DescriptionINFOID:0000000005147963
When the sensor rotor rotates, the magnetic field changes. It converts the magnetic field changes to current
signals (rectangular wave) and transmits them to t he ABS actuator and electric unit (control unit).
DTC LogicINFOID:0000000005147964
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to BRC-28, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000005147965
Regarding Wiring Diagram information, refer to BRC-92, "Wiring Diagram - BRAKE CONTROL SYSTEM -".
CAUTION:
Do not check between wheel sensor terminals.
1.CONNECTOR INSPECTION
1. Disconnect the ABS actuator and electric unit (contro l unit) connector and wheel sensor of malfunctioning
code.
2. Check the terminals for deformati on, disconnection, looseness or damage.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair or replace as necessary.
2.CHECK WHEEL SENSOR OUTPUT SIGNAL
1. Connect ABS active wheel sensor tester (J-45741) to wheel sensor using appropriate adapter.
2. Turn on the ABS active wheel sensor tester power switch.
DTC Display item Malfunction detected condition Possible cause
C1101 RR RH SENSOR-1 Circuit of rear RH wheel sensor is open. Or when the sen-
sor power voltage is outside the standard.
• Harness or connector
• Wheel sensor
• ABS actuator and electric unit (control unit)
C1102 RR LH SENSOR-1
Circuit of rear LH wheel sensor is open. Or when the sen-
sor power voltage is outside the standard.
C1103 FR RH SENSOR-1 Circuit of front RH wheel sensor is open. Or when the
sensor power voltage is outside the standard.
C1104 FR LH SENSOR-1 Circuit of front LH wheel sensor is open. Or when the
sensor power voltage is outside the standard.
Self-diagnosis results
RR RH SENSOR-1RR LH SENSOR-1
FR RH SENSOR-1 FR LH SENSOR-1
Revision: April 20092010 QX56