2011 INFINITI QX56 air condition

P1802, P1803, P1804, P1809 TRANSFER CONTROL UNIT
DLN-51
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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DTC/CIRCUIT DIAGNOSIS
P1802, P1803, P1804, P1809 TRANSFER CONTROL UNIT
DTC LogicINFOID:0000000006222244
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”.
Are DTC
′s “P1802, P1803, P1804 or P1809” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-51, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222245
1.PERFORM SELF-DIAGNOSIS
With CONSULT-III
1. Erase self-diagnostic results for “ALL MODE AWD/4WD”.
2. Turn the ignition switch OFF, and then wait 10 seconds and more.
3. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Are DTC
′s “P1802, P1803, P1804 or 1809” detected?
YES >> Replace transfer control unit. Refer to DLN-107, "Removal and Installation".
NO >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace error-detected parts.
DTC Display item Malfunction detected condition Possible cause
P1802 CONTROL UNIT 1 Malfunction is detected in the memory
(RAM) system of transfer control unit.
Internal malfunction of transfer control
unit.
P1803 CONTROL UNIT 2
Malfunction is detected in the memory
(ROM) system of transfer control unit.
P1804 CONTROL UNIT 3 Malfunction is detected in the memory
(EEOROM) system of transfer control
unit.
P1809 CONTROL UNIT 4 AD converter system of transfer control
unit is malfunctioning.
Revision: 2010 May2011 QX56

DLN-52
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P1807 OUT PUT SHAFT SPEED SENSOR
P1807 OUT PUT SHAFT SPEED SENSOR
DTC LogicINFOID:0000000006222246
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 for approximately 1minute.
2. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P1807” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-52, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222247
1.PERFORM TCM SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “TRANSMISSION”.
Is any DTCs detected?
YES >> Check the DTC.
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 A/T CHECK indictor lamp turns OFF.
Does A/T CHECK indicator lamp turn OFF?
YES >> GO TO 3.
NO >> Refer to TM-165, "
Symptom Table".
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
"P1807" 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
P1807 VHCL SPEED SEN-AT  Malfunction is detected in output
speed signal that is output from TCM
through CAN communication.
 Improper signal is input while driving.  Harness or connector (CAN communi-
cation line)
TCM
- Internal malfunction of TCM
- Output speed signal error
Revision: 2010 May2011 QX56

P1808 WHEEL SPEED SENSORDLN-53
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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P1808 WHEEL SPEED SENSOR
DTC LogicINFOID:0000000006222248
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 for approximately 1minute.
2. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P1808” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-53, "DTC Logic".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222249
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
"P1808" 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
P1808 VHCL SPEED SEN-ABS  Malfunction is detected in vehicle
speed signal that is output from ABS
actuator and electric unit (control unit)
through CAN communication.
 Improper signal is input while driving.  Harness or connector (CAN communi-
cation line)
 Malfunction of ABS actuator and elec-
tric unit (control unit)
- Malfunction of ABS actuator and elec-
tric unit (control unit) circuit error
- Vehicle speed signal error
Revision: 2010 May2011 QX56

P180F TRANSFER INTERNAL SPEED SENSORDLN-63
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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5.REPLACE TRANSFER CONTROL ACTUATOR
1. Replace transfer control actuator. Refer to DLN-114, "
Removal and Installation".
2. Perform confirmation procedure again. Refer to DLN-57, "
DTC Logic".
Is DTC
“P180F” detected?
YES >> GO TO 6.
NO >> INSPECTION END
6.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 >> GO TO 7.
NO >> Transfer assembly is mechanical malfunction. Replace transfer assembly. Refer to DLN-121,
"Removal and Installation".
7.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.
Monitor item Condition Status
ROTARY POSI SEN Turn the actuator shaft. Value is changing
Revision: 2010 May2011 QX56

DLN-64
< DTC/CIRCUIT DIAGNOSIS >[TRANSFER: ATX90A]
P1811 POWER SUPPLY CIRCUIT
FOR TRANSFER CONTROL UNIT
P1811 POWER SUPPLY CIRCUIT FOR TRANSFER CONTROL UNIT
DescriptionINFOID:0000000006222260
Supplies power to transfer control unit.
DTC LogicINFOID:0000000006222261
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
“P1811” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-64, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222262
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.
DTC Display item Malfunction detected condition Possible cause
P1811 BATTERY VOLTAGE When transfer control unit power supply
is lower or higher than normalMalfunction of transfer control unit pow-
er supply circuit (open or short)
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

P1813 4WD MODE SWITCHDLN-67
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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P1813 4WD MODE SWITCH
DTC LogicINFOID:0000000006222263
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
“P1813” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-67, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222264
1.CHECK TRANSFER SHIFT SWITCH
Check 4WD switch assembly. Refer to DLN-68, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 2.
NO >> 4WD shift switch is malfunctioning. Replace 4WD switch assembly. Refer to DLN-108, "
Removal
and Installation".
2.CHECK 4WD SHIFT SWITCH CIRCUIT (1)
1. Disconnect transfer control unit harness connector.
2. Check the continuity between transfer control uni t harness connector and 4WD switch assembly harness
connector.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace error-detected parts.
DTC Display item Malfunction detected condition Possible cause
P1813 4WD MODE SW Multiple signals received from 4WD shift
switch are detected. 4WD switch assembly
- Internal malfunction of 4WD switch
assembly
- Malfunction of 4WD switch assembly circuit
 Transfer control unit
Transfer control unit 4WD switch assembly Continuity
Connector Terminal Connector Terminal
E59 11
M54 11 E x i s t e d
10 Not existed 9 Not existed
35 11 N o t e x i s t e d
10 Existed 9 Not existed
14 11 N o t e x i s t e d
10 Not existed 9 Existed
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

P1816 PARKING/NEUTRAL POSITION SWITCHDLN-69
< DTC/CIRCUIT DIAGNOSIS > [TRANSFER: ATX90A]
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P1816 PARKING/NEUTRAL POSITION SWITCH
DTC LogicINFOID:0000000006222266
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC REPRODUCTION PROCEDURE
With CONSULT-III
1. Turn the ignition switch OFF to ON.
2. Shift the A/T shift selector P position.
3. Perform self-diagnosis for “ALL MODE AWD/4WD”.
Is DTC
“P1816” detected?
YES >> Proceed to diagnosis procedure. Refer to DLN-69, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis ProcedureINFOID:0000000006222267
1.PERFORM TCM SELF-DIAGNOSIS
With CONSULT-III
Perform self-diagnosis for “TRANSMISSION”.
Is any DTCs detected?
YES >> Check the DTC.
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 A/T CHECK indictor lamp turns OFF.
Does A/T CHECK indicator lamp turn OFF?
YES >> GO TO 3.
NO >> Refer to TM-165, "
Symptom Table".
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
"P1816" 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
P1816 PNP SW/CIRC Malfunction is detected in PNP switch
signal that is output from TCM through
CAN communication Harness or connector (CAN communi-
cation line)
TCM
- Internal malfunction of TCM
- A/T shift selector error
Revision: 2010 May2011 QX56