2011 INFINITI QX56 engine

DLN-74
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P181B INCOMPLETE SELFSHUT
P181B INCOMPLETE SELFSHUT
DTC LogicINFOID:0000000006222274
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Turn the ignition switch OFF.
2. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P181B” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-74, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222275
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 for 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 GROUND
1. Turn the ignition switch OFF.
DTC Display item Malfunction detected condition Possible cause
P181B IMCOMP SELFSHUT When ignition switch is OFF and transfer
control unit power su
pply is lower or
higher than normal Self-shut is incomplete.
Transfer control unit
—Voltage
Connector Terminal
E59 20 Ground Battery voltage
Transfer control unit —Voltage
Connector Terminal
E59 20 Ground Battery voltage
Revision: 2010 May2011 QX56

P1820 ENGINE SPEED SIGNALDLN-79
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
P1820 ENGINE SPEED SIGNAL
DTC LogicINFOID:0000000006222283
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Start the engine and drive at 20 km/h (12 MPH) or more.
2. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P1820” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-79, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222284
1.PERFORM ECM SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “ENGINE”.
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. Turn the ignition switch OFF.
3. Start the engine and drive vehicle for a while.
4. Check that malfunction indicator lamp (MIL) turns OFF.
Does malfunction indicator lamp (MIL) turn OFF?
YES >> GO TO 3.
NO >> Refer to EC-515, "
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
"P1820" 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
P1820 ENGINE SPEED SIG Malfunction is detected in engine speed
signal that is output from ECM through
CAN communication. Harness or connector (CAN communi-
cation line)
 Internal malfunction of ECM
Revision: 2010 May2011 QX56

DLN-80
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P1826 TRANSFER FLUID TEMPERATURE
P1826 TRANSFER FLUID TEMPERATURE
DTC LogicINFOID:0000000006222285
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Start the engine and drive at 40 km/h (25 MPH) or more for approximately 1minute.
2. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P1826” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-80, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222286
1.CHECK TRANSFER FLUID TEMPER ATURE SENSOR POWER SUPPLY
1. Turn the ignition switch OFF.
2. Disconnect transfer fluid temperature sensor harness connector.
3. Turn the ignition switch ON. CAUTION:
Never start the engine.
4. Check the voltage between transfer fluid temperature sensor harness connector terminals.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK TRANSFER FLUID TE MPERATURE SENSOR CIRCUIT
1. Turn the ignition switch OFF.
2. Disconnect transfer control unit harness connector.
3. Check the continuity between transfer control uni t harness connector and transfer control actuator har-
ness connector.
4. Check the continuity between transfer flui d temperature sensor harness connector and ground.
DTC Display item Malfunction detected condition Possible cause
P1826 OIL TEMP SEN When vehicle speed is 40km/h or more
and transfer fluid temperature is lower
than normal
Transfer fluid temperature
 Malfunction of transfer fluid tempera-
ture sensor circuit (open)
When transfer fluid temperature is high-
er than normal Transfer fluid temperature
 Malfunction of transfer fluid tempera-
ture sensor circuit (short)
+ −
Voltag e
Transfer fluid temperature sensor
Connector Terminal F37 2 1 Approx. 5 V
Transfer control unit Transfer fluid temperature sensor Continuity
Connector Terminal Connector Terminal
E59 7
F37 2
Existed
36 1
Revision: 2010 May2011 QX56

DLN-82
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P1829 ACCELERATOR PEDAL POSITION SENSOR
P1829 ACCELERATOR PEDAL POSITION SENSOR
DTC LogicINFOID:0000000006222288
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
“P1829” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-82, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222289
1.PERFORM ECM SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “ENGINE”.
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. Turn the ignition switch OFF.
3. Start the engine and drive vehicle for a while.
4. Check that malfunction indicator lamp (MIL) turns OFF.
Does malfunction indicator lamp (MIL) turn OFF?
YES >> GO TO 3.
NO >> Refer to EC-515, "
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
"P1829" 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
P1829 THROTTLE POSI SEN Malfunction is detected in accelerator
pedal position signal that is output from
ECM through CAN communication. Harness or connector (CAN communi-
cation line)
 Internal malfunction of ECM
Revision: 2010 May2011 QX56

P182A TRANSFER HI-LO POSITION SENSOR
DLN-83
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
P182A TRANSFER HI-LO POSITION SENSOR
DTC LogicINFOID:0000000006222290
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Start the engine. CAUTION:
Never drive the vehicle.
2. Turn the 4WD shift switch AUTO ⇒4H ⇒4LO ⇒4H ⇒AUTO.
3. Drive at 20 km/h (12MPH) or more for 1 minute or more.
4. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P182A” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-83, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222291
1.CHECK TRANSFER HI-LO POSITION SENSOR SIGNAL
1. Turn the ignition switch ON. CAUTION:
Never start the engine.
2. Check the voltage between transfer control unit harness connector and ground.
CAUTION:
After operating 4WD shift sw itch, move the vehicle back and forth to check voltage.
Is the inspection result normal?
YES >> GO TO 5.
NO >> GO TO 2.
2.CHECK TRANSFER HI-LO POSITION SENSOR POWER SUPPLY
1. Turn the ignition switch OFF.
2. Disconnect transfer Hi-Lo position sensor harness connector.
3. Turn the ignition switch ON. CAUTION:
Never start the engine.
4. Check the voltage between transfer Hi-Lo position sensor harness connector terminals.
DTC Display item Malfunction detected condition Possible cause
P182A HI-LO POSITION SEN Malfunction related to transfer Hi-Lo po-
sition sensor has been detected.Internal malfunction of transfer Hi-Lo po-
sition sensor
+
−Condition Voltage
Transfer control unit
Connector Terminal
E59 6
Ground4WD mode: AUTO or 4H Approx. 0 V
4WD mode: 4L Approx. 5 V
25 4WD mode: AUTO or 4H Approx. 0 V
4WD mode: 4L Approx. 5 V
Revision: 2010 May2011 QX56

P182B TRANSFER LOCK POSITION SENSOR
DLN-85
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
P182B TRANSFER LOCK POSITION SENSOR
DTC LogicINFOID:0000000006222292
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Turn the ignition switch OFF to ON.
2. Turn the 4WD shift switch AUTO ⇒4H ⇒4LO ⇒4H ⇒AUTO.
3. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P182B” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-85, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222293
1.CHECK TRANSFER LOCK POSITION SENSOR
With CONSULT-III
1. Start the engine.
2. Turn the 4WD shift switch AUTO ⇒4H ⇒4LO ⇒4H ⇒AUTO.
3. Check “LOCK POSI SEN” of CONSULT-III “DATA MONITOR” for “ALL MODE AWD/4WD”.
What is the item on "DATA MONITOR"?
OPEN >> GO TO 7.
LOCK >> GO TO 7.
UNLEAN>>GO TO 6.
HI TEMP>>GO TO 5.
ERROR>> GO TO 5.
BAT >> GO TO 2.
GND >> GO TO 2.
2.CHECK TRANSFER LOCK POSITION POWER SUPPLY
1. Turn the ignition switch OFF.
2. Disconnect transfer positi on sensor harness connector.
3. Turn the ignition switch ON. CAUTION:
DTC Display item Malfunction detected condition Possible cause
P182B Lock POSITION SEN Malfunction related to transfer lock posi-
tion sensor has been detected. Transfer lock position sensor
- Transfer lock position sensor error
- Malfunction of transfer lock position
sensor circuit
Monitor item Condition Status
LOCK POSI SEN 4WD shift switch: AUTO or 4H OPEN
4WD shift switch: 4L LOCK
When transfer lock position sensor is unlearned. UNLEAN
When the temperature of transfer lock position sensor is
high.
HI TEMP
When transfer lock position sensor is malfunctioning. ERROR
When transfer lock position sensor signal circuit is short.
(Battery short) BAT
When transfer lock position sensor signal circuit is short.
(Ground short) GND
Revision: 2010 May2011 QX56

DLN-86
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P182B TRANSFER LOCK POSITION SENSOR
Never start the engine.
4. Check the voltage between transfer position sensor harness connector terminals.
Is the inspection result normal?
YES >> GO TO 4.
NO >> GO TO 3.
3.CHECK TRANSFER LOCK POSITION SENSOR POWER SUPPLY CIRCUIT
1. Turn the ignition switch OFF.
2. Disconnect transfer control unit harness connector.
3. Check the continuity between transfer control uni t harness connector and transfer lock position sensor
harness connector.
4. Check the continuity between transfer lock position harness connector and ground.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Repair or replace error-detected parts.
4.CHECK TRANSFER LOCK POSITI ON SENSOR SIGNAL CIRCUIT
1. Turn the ignition switch OFF.
2. Disconnect transfer control unit harness connector.
3. Check the continuity between transfer control uni t harness connector and transfer lock position sensor
harness connector.
4. Check the continuity between transfer lock position harness connector and ground.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair or replace error-detected parts.
5.REPLACE TRANSFER LOCK POSITION SENSOR
1. Replace transfer lock position sensor. Refer to DLN-119, "
Removal and Installation".
2. Perform confirmation procedure again. Refer to DLN-85, "
DTC Logic".
Is the inspection result normal?
+ −
Voltag e
Transfer lock position sensor
Connector Terminal F40 1 2 Approx. 5 V
Transfer control unit Transfer lock position sensor Continuity
Connector Terminal Connector Terminal
E59 17
F40 1
Existed
30 2
Transfer lock position sensor -Continuity
Connector Terminal
F40 1 Ground Not existed
Transfer control unit Transfer lock position sensor Continuity
Connector Terminal Connector Terminal
E59 38 F40 3 Existed
Transfer lock position sensor -Continuity
Connector Terminal
F40 3 Ground Not existed
Revision: 2010 May2011 QX56

DLN-88
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P1830 ABS OPERATION SIGNAL
P1830 ABS OPERATION SIGNAL
DTC LogicINFOID:0000000006222294
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
“P1830” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-88, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222295
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-123, "
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
"P1830" 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
P1830 ABS OP SIG Malfunction is detect
ed in ABS operation
signal that is outp ut from ABS actuator
and electric unit (control unit) through
CAN communication. Malfunction of ABS system
Revision: 2010 May2011 QX56