ground INFINITI QX56 2011 Factory Service Manual

P1811 POWER SUPPLY CIRCUIT FOR TRANSFER CONTROL UNIT
DLN-65
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
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.
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 CONTROL UNIT GROUND
1. Turn the ignition switch OFF.
2. Check the continuity between transfer control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair or replace error-detected parts.
6.CHECK TERMINALS AND HARNESS CONNECTORS
Transfer control unit — Voltage
Connector Terminal
E59 32 Ground 0 V
Transfer control unit — Voltage
Connector Terminal
E59 32 Ground Battery voltage
IPDM E/R Transfer 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 —Continuity
Connector Terminal
E60 46
Ground Existed
44
Revision: 2010 May2011 QX56

DLN-68
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P1813 4WD MODE SWITCH
3.CHECK 4WD SHIFT SWITCH CIRCUIT (2)
Check the continuity between 4WD switch assembly harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
4.CHECK TERMINALS AND HARNESS CONNECTORS
 Check transfer control unit pin terminals for damage or loose connection with harness connector.
 Check 4WD switch assembly pin terminals fo r damage or loose connection with harness connector.
Is the inspection result normal?
YES >> Replace transfer control unit. Refer to DLN-107, "Removal and Installation".
NO >> Repair or replace error-detected parts.
Component InspectionINFOID:0000000006222265
1.CHECK 4WD SHIFT SWITCH
1. Turn the ignition switch OFF.
2. Remove 4WD switch assembly. Refer to DLN-108, "
Removal and Installation".
3. Check the continuity between 4WD switch assembly harness connector terminals.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace 4WD switch assembly. Refer to DLN-108, "
Removal and Installation".
4WD switch assembly
—Continuity
Connector Terminal
M54 11
Ground Not existed
10
9
4WD switch assembly Condition Continuity
Te r m i n a l
12 9 4WD shift switch: AUTO Existed
4WD shift switch: 4H or 4L Not existed
12 10 4WD shift switch: 4H Existed
4WD shift switch: AUTO or 4L Not existed
12 11 4WD shift switch: 4L Existed
4WD shift switch: AUTO or 4H Not existed
Revision: 2010 May2011 QX56

DLN-70
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P1817 TRANSFER MOTOR
P1817 TRANSFER MOTOR
DTC LogicINFOID:0000000006222268
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
“P1817” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-70, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222269
1.CHECK TRANSFER MOTOR CIRCUIT (1)
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 control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair or replace error-detected parts.
2.CHECK TRANSFER MOTOR
Check the transfer control actuator. Refer to DLN-71, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 3.
NO >> Transfer motor is malfunctioning. Repl ace transfer control actuator. Refer to DLN-114, "
Removal
and Installation".
3.CHECK TRANSFER INTERNAL FUNCTION
With CONSULT-III
1. Remove transfer control actuator. Refer to DLN-114, "
Removal and Installation".
DTC Display item Malfunction detected condition Possible cause
P1817 SHIFT ACTUATOR Malfunction is detected in transfer motor. Transfer control actuator
 Transfer motor error
 malfunction of transfer motor circuit
Transfer control unit Transfer control actuator
Continuity
Connector Terminal Connector Terminal
E60 45
F52 8
Existed
43 1
Transfer control unit —Continuity
Connector Terminal
E60 45
Ground Not existed
43
Revision: 2010 May2011 QX56

DLN-72
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P181A TRANSFER MOTOR TEMPERATURE SENSOR
P181A TRANSFER MOTOR TEMPERATURE SENSOR
DTC LogicINFOID:0000000006222271
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
“P181A” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-72, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222272
1.CHECK TRANSFER MOTOR TEMPERATURE SENSOR POWER SUPPLY
1. Turn the ignition switch OFF.
2. Disconnect transfer control actuator harness connector.
3. Turn the ignition switch ON. CAUTION:
Never start the engine.
4. Check the voltage between transfer contro l actuator harness connector terminals.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK TRANSFER MOTOR TEMPERATURE 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 control actuator harness connector and ground.
DTC Display item Malfunction detected condition Possible cause
P181A MOTOR TEMP SEN When vehicle speed is 40km/h or more
and transfer motor temperature is lower
than normal
Transfer control actuator
 Malfunction of transfer motor temper-
ature sensor circuit. (open)
When transfer motor temperature is
higher than normal Transfer control actuator
 Malfunction of transfer motor temper-
ature sensor circuit. (short)
+ −
Voltag e
Transfer control actuator
Connector Terminal F52 4 7 Approx. 5 V
Transfer control unit Transfer control actuator Continuity
Connector Terminal Connector Terminal
E59 28
F52 4
Existed
97
Revision: 2010 May2011 QX56

P181A TRANSFER MOTOR TEMPERATURE SENSOR
DLN-73
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
3.CHECK TRANSFER MOTOR TEMPERATURE SENSOR
Check the transfer control actuator. Refer to DLN-73, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 4.
NO >> Transfer motor temperature sensor is malfuncti oning. Replace transfer control actuator. Refer to
DLN-114, "
Exploded View".
4.CHECK TERMINALS AND HARNESS CONNECTORS
Check the pin terminals for damage or loose connection with each harness connector.
Is the inspection result normal?
YES >> Replace transfer control unit. Refer to DLN-107, "Removal and Installation".
NO >> Repair or replace error-detected parts.
Component InspectionINFOID:0000000006222273
1.CHECK TRANSFER MOTOR TEMPERATURE SENSOR
1. Turn the ignition switch OFF.
2. Disconnect transfer control actuator harness connector.
3. Check the resistance between transfer cont rol actuator harness connector terminals.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Transfer motor temperature sensor is malfuncti oning. Replace transfer control actuator. Refer to
DLN-114, "
Exploded View".
Transfer control actuator —Continuity
Connector Terminal
F52 7 Ground Not existed
Transfer control actuator Condition Resistance
Te r m i n a l
47 20
°C (68 °F) Approx. 12.5 k Ω
80 °C (176 °F) Approx. 1.3 k Ω
Revision: 2010 May2011 QX56

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

P181B INCOMPLETE SELFSHUTDLN-75
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
2. Check the continuity between transfer control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
4.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
"P181B" is detected, Replace transfer control unit. Refer to DLN-107, "
Removal and Installation".
NO >> Repair or replace error-detected parts.
Transfer control unit —Continuity
Connector Terminal
E60 44
Ground Existed
46
Revision: 2010 May2011 QX56

DLN-76
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P181C TRANSFER MOTOR POWER SUPPLY
P181C TRANSFER MO
TOR POWER SUPPLY
DescriptionINFOID:0000000006222276
Supplies power to transfer control actuator (transfer motor).
DTC LogicINFOID:0000000006222277
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Turn the ignition switch OFF to ON.
2. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P181C” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-76, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222278
1.CHECK TRANSFER MOTOR POWER SUPPLY (2)
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 MOTOR POWER SUPPLY CIRCUIT (2)
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.
3.CHECK TERMINALS AND HARNESS CONNECTORS
Check the pin terminals for damage or loose connection with each harness connector.
Is the inspection result normal?
YES >> 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
P181C MOTOR POWER SUPPLY When transfer control actuator power
supply is lower or higher than normalMalfunction of transfer control actuator
(transfer motor) powe
r supply circuit
+ −
Voltag e
Transfer control unit
Connector Terminal E60 41 46 Battery voltage
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

P1826 TRANSFER FLUID TEMPERATURE
DLN-81
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
3.CHECK TRANSFER FLUID TEMPERATURE SENSOR
Check the transfer fluid temperature sensor. Refer to DLN-81, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 4.
NO >> Replace transfer fluid temperature sensor. Refer to DLN-120, "
Exploded View".
4.CHECK TERMINALS AND HARNESS CONNECTORS
Check the pin terminals for damage or loose connection with each harness connector.
Is the inspection result normal?
YES >> Replace transfer control unit. Refer to DLN-107, "Removal and Installation".
NO >> Repair or replace error-detected parts.
Component InspectionINFOID:0000000006222287
1.CHECK TRANSFER FLUID TEMPERATURE SENSOR
1. Turn the ignition switch OFF.
2. Disconnect transfer fluid temper ature sensor harness connector.
3. Check the resistance between transfer control fluid temperature sensor connector terminals.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Replace transfer fluid temperature sensor. Refer to DLN-120, "
Exploded View".
Transfer fluid temperature sensor
—Continuity
Connector Terminal
F37 2 Ground Not existed
Transfer fluid temperature sensor Condition Resistance
Te r m i n a l
21 20
°C (68 °F) Approx. 2.5 k Ω
80 °C (176 °F) Approx. 0.3 k Ω
Revision: 2010 May2011 QX56