2011 INFINITI QX56 engine

P1831 VDC OPERATION SIGNALDLN-89
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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P1831 VDC OPERATION SIGNAL
DTC LogicINFOID:0000000006222296
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Start the engine and drive at 30 km/h (19 MPH) or more.
2. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P1831” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-89, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222297
1.PERFORM ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “ABS”.
Is any DTCs detected?
YES >> Check the DTCs.
NO >> GO TO 2.
2.ERASE SELF-DIAGNOSTIC RESULT
With CONSULT-III
1. Erase self-diagnostic results for “ALL MODE AWD/4WD”.
2. Start the engine and drive vehicle at 30 km/h (19 MPH) or more.
3. Check that ABS warning lamp turns OFF.
Does ABS warning lamp turn OFF?
YES >> GO TO 3.
NO >> Refer to BRC-122, "
Diagnosis Procedure".
3.CHECK TERMINALS AND HARNESS CONNECTORS
Check transfer control unit pin terminals for damage or loose connection with harness connector.
Is inspection result normal?
YES >> After turning the ignition switch OFF, perform DTC confirmation procedure again. When DTC
"P1831" is detected, Replace transfer control unit. Refer to DLN-107, "
Removal and Installation".
NO >> Repair or replace error-detected parts.
DTC Display item Malfunction detected condition Possible cause
P1831 VDC OP SIG Malfunction is detected in VDC opera-
tion signal that is output from ABS actu-
ator and electric unit (control unit)
through CAN communication.Malfunction of ABS system
Revision: 2010 May2011 QX56

DLN-90
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P1832 TCS OPERATION SIGNAL
P1832 TCS OPERATION SIGNAL
DTC LogicINFOID:0000000006222298
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Start the engine and drive at 30 km/h (19 MPH) or more.
2. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P1832” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-90, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222299
1.PERFORM ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “ABS”.
Is any DTCs detected?
YES >> Check the DTCs.
NO >> GO TO 2.
2.ERASE SELF-DIAGNOSTIC RESULT
With CONSULT-III
1. Erase self-diagnostic results for “ALL MODE AWD/4WD”.
2. Start the engine and drive vehicle at 30 km/h (19 MPH) or more.
3. Check that ABS warning lamp turns OFF.
Does ABS warning lamp turn OFF?
YES >> GO TO 3.
NO >> Refer to BRC-122, "
Diagnosis Procedure".
3.CHECK TERMINALS AND HARNESS CONNECTORS
Check transfer control unit pin terminals for damage or loose connection with harness connector.
Is inspection result normal?
YES >> After turning the ignition switch OFF, perform DTC confirmation procedure again. When DTC
"P1832" is detected, Replace transfer control unit. Refer to DLN-107, "
Removal and Installation".
NO >> Repair or replace error-detected parts.
DTC Display item Malfunction detected condition Possible cause
P1832 TCS OP SIG Malfunction is detected in TCS operation
signal that is outp
ut from ABS actuator
and electric unit (control unit) through
CAN communication. Malfunction of TCS system
Revision: 2010 May2011 QX56

POWER SUPPLY AND GROUND CIRCUITDLN-93
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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POWER SUPPLY AND GROUND CIRCUIT
DescriptionINFOID:0000000006222306
Supplies power to 4WD system.
Diagnosis ProcedureINFOID:0000000006222307
1.CHECK TRANSFER CONTROL UNIT POWER SUPPLY (1)
1. Turn the ignition switch OFF.
2. Disconnect transfer control unit harness connector.
3. Check the voltage between transfer control unit harness connector and ground.
4. Turn the ignition switch ON. CAUTION:
Never start the engine.
5. Check the voltage between transfer control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK TRANSFER CONTROL UNIT POWER SUPPLY (2)
1. Turn the ignition switch OFF.
2. Check the 10A fuse (#34).
3. Check the harness for open or short between transfe r control unit harness connector No.20 terminal and
10A (#34).
Is the inspection result normal?
YES >> Perform the trouble diagnosis fo r power supply circuit. Refer to PG-11, "Wiring Diagram - BAT-
TERY POWER SUPPLY -".
NO >> Repair or replace error-detected parts.
3.CHECK TRANSFER CONTROL UNIT POWER SUPPLY (3)
1. Turn the ignition switch OFF.
2. Check the voltage between transfer control unit harness connector and ground.
3. Turn the ignition switch ON. CAUTION:
Never start the engine.
4. Check the voltage between transfer control unit harness connector and ground.
Transfer control unit — Voltage
Connector Terminal
E59 20 Ground Battery voltage
Transfer control unit — Voltage
Connector Terminal
E59 20 Ground Battery voltage
Transfer control unit — Voltage
Connector Terminal
E59 32 Ground Approx. 0 V
Transfer control unit — Voltage
Connector Terminal
E59 32 Ground Battery voltage
Revision: 2010 May2011 QX56

DLN-94
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
POWER SUPPLY AND GROUND CIRCUIT
Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 4.
4.CHECK TRANSFER CONTROL UNIT POWER SUPPLY (4)
1. Turn the ignition switch OFF.
2. Check the 10A fuse (#56).
3. Disconnect IPDM E/R harness connector.
4. Check the continuity between transfer control unit harness connector and IPDM E/R harness connector.
5. Check the continuity between transfer control unit harness connector and the ground.
Is the inspection result normal?
YES >> Perform the trouble diagnosis for ignition power supply circuit. Refer to PG-89, "Wiring Diagram -
IGNITION POWER SUPPLY -".
NO >> Repair or replace error-detected parts.
5.CHECK TRANSFER MOTOR POWER SUPPLY
1. Turn the ignition switch OFF.
2. Check the voltage between transfer control unit harness connector and ground.
3. Turn the ignition switch ON. CAUTION:
Never start the engine.
4. Check the voltage between transfer control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 7.
NO >> GO TO 6.
6.CHECK TRANSFER MOTOR POWER SUPPLY CIRCUIT
1. Turn the ignition switch OFF.
2. Check the 30A fusible link (J).
3. Check the harness for open or short between transfe r control unit harness connector No.41 terminal and
30A fusible link (J).
Is the inspection result normal?
YES >> Perform the trouble diagnosis for power supply circuit. Refer to PG-11, "Wiring Diagram - BAT-
TERY POWER SUPPLY -".
NO >> Repair or replace error-detected parts.
7.CHECK 4WD SWITCH ASSEMBLY POWER SUPPLY (1)
1. Turn the ignition switch OFF.
IPDM E/R Transfe r control unit
Continuity
Connector Terminal Connector Terminal
E15 58 E59 32 Existed
Transfer control unit —Continuity
Connector Terminal
E59 32 Ground Not existed
Transfer control unit —Voltage
Connector Terminal
E60 41 Ground Battery voltage
Transfer control unit —Voltage
Connector Terminal
E60 41 Ground Battery voltage
Revision: 2010 May2011 QX56

POWER SUPPLY AND GROUND CIRCUITDLN-95
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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2. Disconnect 4WD switch assembly harness connector.
3. Check the voltage between 4WD switch assembly harness connector and ground.
4. Turn the ignition switch ON. CAUTION:
Never start the engine.
5. Check the voltage between 4WD switch assembly harness connector and ground.
Is the inspection result normal?
YES >> GO TO 9.
NO >> GO TO 8.
8.CHECK 4WD SWITCH ASSEMBLY POWER SUPPLY (2)
1. Turn the ignition switch OFF.
2. Check the 10A fuse (#13).
3. Disconnect fuse block (J/B) harness connector.
4. Check the continuity between transfer control unit harness connector and IPDM E/R harness connector.
5. Check the continuity between transfer control unit harness connector and the ground.
Is the inspection result normal?
YES >> Perform the trouble diagnosis for ignition power supply circuit. Refer to PG-89, "Wiring Diagram -
IGNITION POWER SUPPLY -".
NO >> Repair or replace error-detected parts.
9.CHECK TRANSFER CONTROL UNIT GROUND
1. Turn the ignition switch OFF.
2. Check the voltage between transfer control unit harness connector and ground.
3. Check the continuity between transfer control unit harness connector and ground.
4WD switch assembly — Voltage
Connector Terminal
M54 12 Ground Approx. 0 V
4WD switch assembly — Voltage
Connector Terminal
M54 12 Ground Battery voltage
Fuse block (J/B) 4WD switch assembly Continuity
Connector Terminal Connector Terminal
M3 10C M54 12 Existed
4WD switch assembly —Continuity
Connector Terminal
M54 12 Ground Not existed
Transfer control unit — Voltage
Connector Terminal
E60 44
Ground Approx. 0 V
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Transfer control unit —Continuity
Connector Terminal
E60 44
Ground Existed
46
Revision: 2010 May2011 QX56

4WD WARNING LAMPDLN-97
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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4WD WARNING LAMP
Component Function CheckINFOID:0000000006222308
1.CHECK 4WD WARNING LAMP FUNCTION
1. Turn the ignition switch OFF to ON.
2. Check that 4WD warning lamp light up.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Proceed diagnosis procedure. Refer to DLN-97, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006222309
1.CHECK POWER SUPPLY AND GROUND CIRCUIT
Perform the trouble diagnosis for power supply and ground circuit. Refer to DLN-64, "
Diagnosis Procedure".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace the error-detected parts.
2.PERFORM SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is any DTC detected?
YES >> Check the DTC.
NO >> GO TO 3.
3.CHECK 4WD WARNING LAMP SIGNAL
With CONSULT-III
1. Turn the ignition switch ON. CAUTION:
Never start the engine.
2. Check “4WD FAIL LAMP” of CONSULT-III “DATA MONITOR” for “ALL MODE AWD/4WD”.
Does the item on
“DATA MONITOR” indicate “On”?
YES >> Check combination meter. Refer to MWI-64, "COMBINATION METER : Diagnosis Procedure".
NO >> Replace transfer control unit. Refer to DLN-107, "
Removal and Installation".
Revision: 2010 May2011 QX56

DLN-98
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
4WD INDICATOR LAMP
4WD INDICATOR LAMP
Component Function CheckINFOID:0000000006222310
1.CHECK 4WD MODE INDICATOR LAMP FUNCTION
1. Start the engine CAUTION:
Never drive the vehicle.
2. Turn the 4WD shift switch AUTO ⇒4H ⇒4LO ⇒4H ⇒AUTO.
3. Check the 4WD shift switch position (“AUTO”, “4H” and “4L”) and the indication of the 4WD mode indica-
tor lamp mutually coincide.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Proceed to diagnosis procedure. Refer to DLN-98, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000006222311
1.CHECK POWER SUPPLY AND GROUND CIRCUIT
Perform the trouble diagnosis for power supply and ground circuit. Refer to DLN-64, "
Diagnosis Procedure".
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace the error-detected parts.
2.CHECK 4WD WARNING LAMP SIGNAL
With CONSULT-III
1. Strat the engine.
CAUTION:
Never drive the vehicle.
2. Turn the 4WD shift switch AUTO ⇒4H ⇒4LO ⇒4H ⇒AUTO.
3. Check “4WD MODE IND” of CONSULT-III “DATA MONITOR” for “ALL MODE AWD/4WD”.
Is the inspection result normal?
YES >> Check combination meter. Refer to MWI-64, "COMBINATION METER : Diagnosis Procedure".
NO >> Replace transfer control unit. Refer to DLN-107, "
Removal and Installation".
Monitor item Condition Status
4WD MODE IND 4WD shift switch: AUTO AUTO
4WD shift switch: 4H 4H
4WD shift switch: 4L 4L
Revision: 2010 May2011 QX56

HEAVY TIGHT-CORNER BRAKING SYMPTOM OCCURS
DLN-99
< SYMPTOM DIAGNOSIS > [TRANSFER: ATX90A]
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SYMPTOM DIAGNOSIS
HEAVY TIGHT-CORNER BRAKING SYMPTOM OCCURS
DescriptionINFOID:0000000006222312
Heavy tight-corner braking symptom o ccurs when the vehicle is driven and the steering wheel is turned fully to
either side after the engine is started.
NOTE:
Light tight-corner braking symptom may occur dependi ng on driving conditions. This is not malfunction.
Diagnosis ProcedureINFOID:0000000006222313
1.PERFORM ECM SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “ECM”.
Is any DTC detected?
YES >> Check the DTC. Refer to EC-98, "DTC Index".
NO >> GO TO 2.
2.PERFORM SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is any DTC detected?
YES >> Check the DTC. Refer to DLN-29, "DTC Index".
NO >> GO TO 3.
3.CHECK TRANSFER INTERNAL FUNCTION
With CONSULT-III
1. Remove transfer control actuator. Refer to DLN-114, "
Removal and Installation".
2. Turn the actuator shaft. Refer to DLN-114, "
Inspection".
3. Check “ROTARY POSI SEN” of CONSULT-II I “DATA MONITOR” for “ALL MODE AWD/4WD”.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Transfer assembly is mechanical malfunction. Replace transfer assembly. Refer to DLN-121,
"Removal and Installation".
Monitor item Condition Status
ROTARY POSI SEN Turn the actuator shaft. Value is changing
Revision: 2010 May2011 QX56