INFINITI QX56 2008 Factory Service Manual

BRC-74
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1178, C1181, C1184, C1
189 ABS ACTIVE BOOSTER
1. Measure the continuity between ABS actuator and electric unit
(control unit) harness connector E125 (A) and active booster
harness connector E49 (B).
2. Measure the continuity between ABS actuator and el ectric unit (control unit) harness connector E125 (A)
and body ground.
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace harness or connector.
3.ACTIVE BOOSTER INSPECTION
1. Reconnect the active booster and ABS actuator and electric unit (control unit) connectors.
2. Use “DATA MONITOR” to check if the status of “RELEASE SWITCH NO” and “RELEASE SWITCH NC” is
normal.
Is the inspection result normal?
YES >> Replace the ABS actuator and electric unit (control unit). Refer to BRC-116, "Removal and Instal-
lation".
NO >> Replace the active booster. Refer to BR-26, "
Removal and Installation".
Component InspectionINFOID:0000000001686343
1.CHECK DATA MONITOR
Use “DATA MONITOR” to check if the status of “RELEASE SWITCH NO” and “RELEASE SWITCH NC” is nor-
mal.
ABS actuator and electric unit (control unit) Active booster
Continuity
Connector Terminal Connector Terminal
A: E125 17
B: E49 3
Ye s
27
1
28 5
30 2
31 4
ABS actuator and electric unit (control unit) —Contin u it y
Connector Terminal
A: E125 17
Ground No
27
28
30
31
AWFIA0028ZZ
Condition
RELEASE SWITCH NO
(DATA MONITOR) RELEASE SWITCH NC
(DATA MONITOR)
When brake pedal is depressed. ONOFF
When brake pedal is released. OFFON
ConditionRELEASE SWITCH NO
(DATA MONITOR) RELEASE SWITCH NC
(DATA MONITOR)
When brake pedal is depressed. ONOFF
When brake pedal is released. OFFON
Revision: March 2010 2008 QX56

C1178, C1181, C1184, C1189 ABS ACTIVE BOOSTER
BRC-75
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
C
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G H
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M A
B
BRC
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Is the inspection result normal?
YES >> Inspection End
NO >> Go to diagnosis procedure. Refer to BRC-73, "
Diagnosis Procedure".
Special Repair RequirementINFOID:0000000001691162
1.ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Always perform neutral position adjustment for the st eering angle sensor when replacing the ABS actuator
and electric unit (control unit). Refer to BRC-8, "
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL
POSITION : Description".
>> GO TO 2
2.CALIBRATION OF DECEL G SENSOR
Always perform calibration of decel G sensor when replacing the ABS actuator and electric unit (control unit).
Refer to BRC-9, "
CALIBRATION OF DECEL G SENSOR : Description".
>> END
Revision: March 2010 2008 QX56

BRC-76
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1179 ABS DELTA S SEN NG
C1179 ABS DELTA S SEN NG
DescriptionINFOID:0000000001686345
The active brake booster consists of a vacuum booster, an active booster control group and a delta stroke
sensor. If a brake booster system malfunction occurs due
to loss of vacuum, the delta stroke sensor will signal
the ABS actuator and electric unit (c ontrol unit) that a booster malfunction has occurred. The active booster
then applies supplemental force to the master cylinder re lative to the amount of force exerted on the brake
pedal.
DTC LogicINFOID:0000000001686346
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-76, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000001686347
INSPECTION PROCEDURE
1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the delta stroke sensor connector E114 and ABS actuator and electric unit (control unit) con- nector E125 and inspect the terminals for def ormation, disconnection, looseness, or damage.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair connector.
2.DELTA STROKE SENSOR CIRCUIT INSPECTION
1. Measure the continuity between ABS actuator and electric unit (control unit) harness connector E125 (A) and delta stroke sen-
sor harness connector E114 (B).
2. Measure the continuity between ABS actuator and el ectric unit (control unit) harness connector E125 (A)
and body ground.
DTC Display item Malfunction detected condition Possible cause
C1179 ABS DELTA S SEN NG Delta stroke sensor is malfunctioning, or signal line of
delta stroke sensor is open or shorted. • Harness or connector
• Delta stroke sensor
• ABS actuator and electric unit
(control unit)
Self-diagnosis results
ABS DELTA S SEN NG
ABS actuator and electric unit (control unit) Delta stroke sensor
Continuity
Connector Terminal Connector Terminal
A: E125 26
B: E114 1
Ye s
39 3
40 5
AWFIA0029ZZ
Revision: March 2010 2008 QX56

C1179 ABS DELTA S SEN NGBRC-77
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace harness or connector.
3.DELTA STROKE SENSOR INSPECTION
1. Reconnect the delta stroke sensor and ABS act uator and electric unit (control unit) connectors.
2. Use “DATA MONITOR” to check if the status of “DELTA S SEN” is normal.
Is the inspection result normal?
YES >> Replace the ABS actuator and elec tric unit (control unit). Refer to BRC-116, "Removal and Instal-
lation".
NO >> Replace the delta stroke sensor.
Component InspectionINFOID:0000000001686348
1.CHECK DATA MONITOR
Use “DATA MONITOR” to check if the status of “DELTA S SEN” is normal.
Is the inspection result normal?
YES >> Inspection End
NO >> Go to diagnosis procedure. Refer to BRC-76, "
Diagnosis Procedure".
Special Repair RequirementINFOID:0000000001691163
1.ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Always perform neutral position adjustment for the st eering angle sensor when replacing the ABS actuator
and electric unit (control unit). Refer to BRC-8, "
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL
POSITION : Description".
>> GO TO 2
2.CALIBRATION OF DECEL G SENSOR
Always perform calibration of decel G sensor when replacing the ABS actuator and electric unit (control unit).
Refer to BRC-9, "
CALIBRATION OF DECEL G SENSOR : Description".
>> END
ABS actuator and electric unit (control unit) —Continuity
Connector Terminal
A: E125 26
Ground No
39
40
Condition DELTA S SEN
(DATA MONITOR)
When brake pedal is depressed. 1.05–1.80 mm
When brake pedal is released. 0.00 mm (+0.6/-0.4)
ConditionDELTA S SEN
(DATA MONITOR)
When brake pedal is depressed. 1.05–1.80 mm
When brake pedal is released. 0.00 mm (+0.6/-0.4)
Revision: March 2010 2008 QX56

BRC-78
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1185 ICC UNIT
C1185 ICC UNIT
DescriptionINFOID:0000000001691164
When the force applied to brake pedal exceeds a certain level, the brake assist is activated and generates a
greater braking force than that of a convent
ional brake booster, even with light pedal force.
When the ICC preview function identifies the need to apply the sudden brake by sensing the vehicle ahead in
the same lane and the distance and relative speed from it, it applies the brake pre-pressure before driver
depresses the brake pedal and improves brake response by reducing its free play.
DTC LogicINFOID:0000000001691165
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-78, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000001691166
INSPECTION PROCEDURE
1.SELF-DIAGNOSIS RESULT CHECK
Perform self-diagnosis of ICC unit.
Are self-diagnosis result items displayed?
YES >> After checking and repairing the applicable item, perform ICC unit self-diagnosis again.
NO >> GO TO 2
2.CONNECTOR INSPECTION
Disconnect the ABS actuator and electric unit (contro l unit) connector and the ICC unit connector and check
the terminals for deformation, disconnection, looseness or damage.
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace as necessary.
3.ICC UNIT CIRCUIT INSPECTION
DTC Display item Malfunction detected condition Possible cause
C1185 ABS ACC CU INTERNAL NG ICC cont rol unit internal malfunction.• Harness or connector
• ICC unit
• ABS actuator and electric unit
(control unit)
Self-diagnosis results
ABS ACC CU INTERNAL NG
Revision: March 2010 2008 QX56

C1185 ICC UNITBRC-79
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
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M A
B
BRC
N
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1. Measure the continuity between ABS actuator and electric unit
(control unit) connector E125 and ICC unit connector B13.
2. Measure the continuity between ABS actuator and electric unit
(control unit) connector E125 and body ground.
Is the inspection result normal?
YES >> Replace ABS actuator and electric unit (control unit). Refer to BRC-116, "Removal and Installa-
tion".
NO >> Repair or replace harness or connector.
Special Repair RequirementINFOID:0000000001691167
1.ADJUSTMENT OF STEERING AN GLE SENSOR NEUTRAL POSITION
Always perform neutral position adjustment for the st eering angle sensor when replacing the ABS actuator
and electric unit (control unit). Refer to BRC-8, "
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL
POSITION : Description".
>> GO TO 2
2.CALIBRATION OF DECEL G SENSOR
Always perform calibration of decel G sensor when replacing the ABS actuator and electric unit (control unit).
Refer to BRC-9, "
CALIBRATION OF DECEL G SENSOR : Description".
>> END
ABS actuator and electric unit (control unit) ICC unit
Continuity
Connector Terminal Connector Terminal
A: E125 7B: B13 10Yes
ABS actuator and electric unit (control unit) —Con tin uit y
Connector Terminal
A: E125 7Ground No
AWFIA0067ZZ
Revision: March 2010 2008 QX56

BRC-80
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
U1000 CAN COMM CIRCUIT
U1000 CAN COMM CIRCUIT
DescriptionINFOID:0000000001686350
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication s
peed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CA N communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
DTC LogicINFOID:0000000001686351
DTC DETECTION LOGIC
Diagnosis ProcedureINFOID:0000000001686352
INSPECTION PROCEDURE
1.CHECK CONNECTOR
1. Turn ignition switch OFF, disconnect the ABS actuat or and electric unit (control unit) connector, and check
the terminals for deformation, disconnection, looseness, and so on. If there is a malfunction, repair or
replace the terminal.
2. Reconnect connector and perform self-diagnosis.
Is
“CAN COMM CIRCUIT” displayed in self-diagnosis display items?
YES >> Print out the self-diagnostic results, and refer to LAN-14, "Trouble Diagnosis Flow Chart".
NO >> Connector terminal is loose, damaged, open, or shorted.
Special Repair RequirementINFOID:0000000001691168
1.ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Always perform neutral position adjustment for the st eering angle sensor when replacing the ABS actuator
and electric unit (control unit). Refer to BRC-8, "
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL
POSITION : Description".
>> GO TO 2
2.CALIBRATION OF DECEL G SENSOR
Always perform calibration of decel G sensor when replac ing the ABS actuator and electric unit (control unit).
Refer to BRC-9, "
CALIBRATION OF DECEL G SENSOR : Description".
>> END
DTC Display item Malfunction detected condition Possible cause
U1000 CAN COMM CIRCUIT When ABS actuator and electric unit (control unit) is not
transmitting or receiving CAN communication signal for 2
seconds or more. • CAN communication line
• ABS actuator and electric unit
(control unit)
Revision: March 2010 2008 QX56

VDC OFF SWITCHBRC-81
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
C
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M A
B
BRC
N
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VDC OFF SWITCH
DescriptionINFOID:0000000001686354
VDC OFF switch can deactivate (t urn OFF) the VDC/TCS function by pressing the VDC OFF switch.
Component Function CheckINFOID:0000000001686355
1.CHECK VDC OFF SWITCH OPERATION
Turn ON/OFF the VDC OFF switch and check that the VDC OFF indicator lamp in the combination meter turns
ON/OFF correctly.
Is the inspection result normal?
YES >> Inspection End
NO >> Go to diagnosis procedure. Refer to BRC-81, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000001686356
1.CHECK VDC OFF SWITCH
1. Turn ignition switch OFF.
2. Disconnect VDC OFF switch connector.
3. Check continuity between VDC OFF switch terminals.
Is the inspection result normal?
YES >> GO TO 2
NO >> Replace VDC OFF switch.
2.CHECK VDC OFF SWITCH HARNESS
1. Disconnect ABS actuator and electric unit (control unit) connec- tor.
2. Check continuity between ABS actuator and electric unit (control unit) connector E125 (A) and VDC OFF switch connector M253
(B).
3. Check continuity between ABS actuator and electric unit (control unit) connector E125 (A) and ground.
Is the inspection result normal?
YES >> GO TO 3
Condition VDC OFF indicator lamp illumination status
VDC OFF switch: ON ON
VDC OFF switch: OFF OFF
VDC OFF switch
Condition Continuity
Te r m i n a l
1 − 2 When VDC OFF switch is pressed. Yes
When VDC OFF switch is released. No
PFIA0307E
ABS actuator and electric unit
(control unit) VDC OFF switch
Continuity
Connector Terminal Connector Terminal
A: E125 38B: M253 1Yes
ABS actuator and electric unit (control unit) —Contin u it y
Connector Terminal
A: E125 38Ground No
AWFIA0030ZZ
Revision: March 2010 2008 QX56

BRC-82
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
VDC OFF SWITCH
NO >> Repair or replace harness.
3.CHECK VDC OFF SWITCH GROUND
Check continuity between VDC OFF switch connector M253 and
ground.
Is the inspection result normal?
YES >> GO TO 4
NO >> Repair or replace harness.
4.CHECK COMBINATION METER
Check if the indication and operation of combination meter are normal. Refer to MWI-24, "
Diagnosis Descrip-
tion".
Is the inspection result normal?
YES >> Replace ABS actuator and electr ic unit (control unit). Refer to BRC-116, "Removal and Installa-
tion".
NO >> Replace combination meter. Refer to MWI-76, "
Removal and Installation".
Component InspectionINFOID:0000000001686357
INSPECTION PROCEDURE
1.CHECK VDC OFF SWITCH
1. Turn ignition switch OFF.
2. Disconnect VDC OFF switch connector.
3. Check continuity between VDC OFF switch terminals.
Is the inspection result normal?
YES >> Inspection End
NO >> Replace VDC OFF switch.
VDC OFF switch —Continuity
Connector Terminal
M253 2Ground Yes
AWFIA0031ZZ
VDC OFF switch
Condition Continuity
Te r m i n a l
1 − 2 When VDC OFF switch is pressed. Yes
When VDC OFF switch is released. No
PFIA0307E
Revision: March 2010
2008 QX56

ABS WARNING LAMPBRC-83
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
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BRC
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ABS WARNING LAMP
DescriptionINFOID:0000000001686358
× : ON –: OFF
Component Function CheckINFOID:0000000001686359
1.CHECK ABS WARNING LAMP OPERATION
Check that the lamp illuminates for approximately 1 second after the ignition switch is turned ON.
Is the inspection result normal?
YES >> Inspection End
NO >> Go to diagnosis procedure. Refer to BRC-83, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000001686360
1.CHECK SELF-DIAGNOSIS
Perform ABS actuator and electric unit (control unit) self-diagnosis. Refer to BRC-24, "
CONSULT-III Function
(ABS)".
Is the inspection result normal?
YES >> GO TO 2
NO >> Check items displayed by self-diagnosis.
2.CHECK COMBINATION METER
Check if the indication and operation of combination meter are normal. Refer to MWI-24, "
Diagnosis Descrip-
tion".
Is the inspection result normal?
YES >> Replace ABS actuator and electric unit (control unit). Refer to BRC-116, "Removal and Installa-
tion".
NO >> Replace combination meter. Refer to MWI-76, "
Removal and Installation".
Condition ABS warning lamp
Ignition switch OFF –
For 1 second after turning ON ignition switch ×
1 second later after turning ON ignition switch –
ABS function is malfunctioning. ×
EBD function is malfunctioning. ×
Revision: March 2010 2008 QX56