2008 INFINITI QX56 ignition

DLN-54
< COMPONENT DIAGNOSIS >[ATX14B]
P1822 CLUTCH PRESSURE SOLENOID
Are the inspection results normal?
YES >> GO TO 7.
NO >> GO TO 2.
2.CHECK HARNESS BETWEEN TRANSFER CONT
ROL UNIT AND CLUTCH PRESSURE SOLENOID
VA LV E
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector, transfer terminal cord assembly harness connector
and transfer dropping resistor.
3. Check continuity between transfer control unit harness connec- tor E142 terminal 19 and transfer terminal cord assembly har-
ness connector F56 terminal 6.
4. Check continuity between transfer dropping resistor harness connector E135 terminal 2 and transfer terminal cord assembly
harness connector F56 terminal 6.
Also check harness for short to ground and short to power.
Are the inspection results normal?
YES >> GO TO 3.
NO >> Repair or replace damaged parts.
3.CHECK HARNESS BETWEEN TRANSFER CONTRO L UNIT AND TRANSFER DROPPING RESISTOR
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and transfer dropping resistor harness connector.
3. Check continuity between transfer control unit harness connec- tor E142 terminal 10 and transfer dropping resistor harness con-
nector E135 terminal 1.
Also check harness for short to ground and short to power.
Are the inspection results normal?
YES >> GO TO 4.
NO >> Repair or replace damaged parts.
4.CHECK GROUND CIRCUIT
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector. Continuity should exist.
SDIA2720E
Continuity should exist.
SDIA2721E
Continuity should exist.
SDIA2722E
Revision: March 2010
2008 QX56

P1822 CLUTCH PRESSURE SOLENOIDDLN-55
< COMPONENT DIAGNOSIS > [ATX14B]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
3. Check continuity between transfer terminal cord assembly har- ness connector F56 terminal 19 and ground.
Also check harness for short to ground and short to power.
Are the inspection results normal?
YES >> GO TO 5.
NO >> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK CLUTCH PRESSURE SOLENOID
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check resistance between transfer terminal cord assembly har- ness connector F56 terminals 6 and 19.
Are the inspection results normal?
YES >> GO TO 6.
NO >> Replace clutch pressure solenoid. Refer to DLN-16,
"Component Parts Location".
6.CHECK TRANSFER DROPPING RESISTOR
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer dropping resistor harness connector.
3. Check resistance between transfer dropping resistor terminals 1 and 2.
Are the inspection results normal?
YES >> GO TO 7.
NO >> Replace transfer dropping resistor.
7.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to DLN-80, "
Reference Value".
Are the inspection results normal?
YES >> GO TO 8.
NO >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
8.CHECK DTC
Drive the vehicle and then perform self-diagnosis.
Are the inspection results normal?
YES >> Inspection End.
NO >> Replace transfer control unit. Refer to DLN-128, "
Removal and Installation".
Component InspectionINFOID:0000000001737146
CLUTCH PRESSURE SOLENOID
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)Continuity should exist.
SDIA2723E
6 - 19 : Approx. 3.0 - 3.4
Ω
SDIA2724E
1 - 2 : Approx. 11.2 - 12.8 Ω
SDIA2725E
Revision: March 2010 2008 QX56

DLN-56
< COMPONENT DIAGNOSIS >[ATX14B]
P1822 CLUTCH PRESSURE SOLENOID
2. Disconnect transfer terminal cord assembly harness connector.
3. Check resistance between transfer terminal cord assembly ter-
minals 6 and 19.
4. If the inspection results are abnormal replace clutch pressure solenoid. Refer to DLN-16, "
Component Parts Location".
TRANSFER DROPPING RESISTOR
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer dropping resistor harness connector.
3. Check resistance between transfer dropping resistor terminals 1
and 2.
4. If the inspection results are abnormal replace transfer dropping resistor. Refer to DLN-16, "
Component Parts Location".
6 - 19 : Approx. 3.0 - 3.4
Ω
WDIA0225E
1 - 2 : Approx. 11.2 - 12.8 Ω
SDIA2725E
Revision: March 2010 2008 QX56

P1823 2-4 SOLENOIDDLN-57
< COMPONENT DIAGNOSIS > [ATX14B]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
P1823 2-4 SOLENOID
DescriptionINFOID:0000000001737147
Proper voltage is not applied to the 2-4WD solenoid valve due to an open or short circuit.
DTC LogicINFOID:0000000001737148
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Perform self-diagnosis.
Is DTC P1823 displayed?
YES >> Perform diagnosis procedure. Refer to DLN-57, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000001737149
1.CHECK 4WD SHIF T SWITCH SYSTEM
Perform self-diagnosis. Refer to DLN-18, "
CONSULT-III Function (ALL MODE AWD/4WD)".
Is the 4WD MOD SW [P1814] (with CO NSULT-III) or Flickering pattern: 16 (without CONSULT-III) detected?
YES >> Perform trouble diagnosis for 4WD shift switch. Refer to DLN-31, "Diagnosis Procedure".
NO >> GO TO 2.
2.CHECK 2-4WD SHIFT SOLENOID SIGNAL
With CONSULT-III
1. Start engine.
2. Select DATA MONITOR mode for ALL MODE AWD/4WD with CONSULT-III.
3. Read out the value of 2-4WD SOL and 2-4WD SOL MON.
DTC CONSULT-III Diagnostic item is detected when... Reference
[P1823] 2-4WD SOLENOID Proper voltage is not applied to 2-4WD
solenoid valve due to open or short cir-
cuit.Refer to DLN-57
.
Monitored
item Condition Display
value
2-4WD SOL • Vehicle stopped
• Engine running
• A/T selector lever N
position
• Brake pedal de- pressed 4WD shift switch: 2WD OFF
4WD shift switch: AUTO
ON
4WD shift switch: 4H
4WD shift switch: 4LO
4WD shift switch: AUTO
(Wait function is operating.) OFF
4WD shift switch: 4H (Wait
function is operating.) OFF
Revision: March 2010
2008 QX56

DLN-58
< COMPONENT DIAGNOSIS >[ATX14B]
P1823 2-4 SOLENOID

Without CONSULT-III
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
Are the inspection results normal?
YES >> GO TO 7.
NO >> GO TO 3.
3.CHECK 4WD SHIFT SWITCH SIGNAL
1. Turn ignition switch ON. (Do not start engine.)
2. Check voltage between transfer control unit harness connector terminals and ground.
Are the inspection results normal?
YES >> GO TO 4.
NO >> Check 4WD shift switch. Refer to DLN-33, "
Component Inspection".
4.CHECK HARNESS BETWEEN 4WD SHIFT SWITCH AND TRANSFER TERMINAL CORD ASSEMBLY
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect 4WD shift switch harness connector and transfer terminal cord assembly harness connector.
2-4WD SOL
MON • Vehicle stopped
• Engine running
• A/T selector lever N
position
• Brake pedal de- pressed 4WD shift switch: 2WD OFF
4WD shift switch: AUTO
ON
4WD shift switch: 4H
4WD shift switch: 4LO
4WD shift switch: AUTO
(Wait function is operating.) OFF
4WD shift switch: 4H (Wait
function is operating.) OFF
Monitored
item Condition Display
value
Connector Terminal ConditionVoltage
(Approx.)
E142 1 -
Ground • Vehicle stopped
• Engine running
• A/T selector lever
N position
• Brake pedal de-
pressed 4WD shift switch: 2WD 0V
4WD shift switch: AU-
TO, 4H or 4LO
Battery
voltage
SDIA2728E
Connector Terminal
ConditionVoltage (Ap-
prox.)
M141 4 - ground 4WD shift switch: AUTO, 4H or 4LO Battery voltage
4WD shift switch: 2WD
0V
SDIA2729E
Revision: March 2010 2008 QX56

P1823 2-4 SOLENOIDDLN-59
< COMPONENT DIAGNOSIS > [ATX14B]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
3. Check continuity between 4WD shift switch harness connector M141 terminal 4 and transfer terminal cord assembly harness
connector F56 terminal 5.
Also check harness for short to ground and short to power.
Are the inspection results normal?
YES >> GO TO 5.
NO >> Repair or replace damaged parts.
5.CHECK HARNESS BETWEEN TRANSF ER CONTROL UNIT AND TRANSFER TERMINAL CORD AS-
SEMBLY
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit har ness connector and transfer terminal cord assembly harness connec-
tor.
3. Check continuity between transfer control unit harness connec- tor E142 terminal 1 and transfer terminal cord assembly harness
connector F56 terminal 4.
Also check harness for short to ground and short to power.
Are the inspection results normal?
YES >> GO TO 6.
NO >> Repair or replace damaged parts.
6.CHECK 2-4WD SOLENOID
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check resistance between transfer terminal cord assembly ter- minals 4 and 5.
Are the inspection results normal?
YES >> GO TO 7.
NO >> Replace 2-4WD solenoid. Refer to DLN-16, "
Compo-
nent Parts Location".
7.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to DLN-80, "
Reference Value".
Are the inspection results normal?
YES >> GO TO 8.
NO >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
8.CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
Are the inspection results normal?
YES >> Inspection End.
NO >> Replace transfer control unit. Refer to DLN-128, "
Removal and Installation".
Continuity should exist.
SDIA2731E
Continuity should exist.
SDIA2732E
4 - 5 : Approx. 22.8 - 25.2
Ω
WDIA0187E
Revision: March 2010 2008 QX56

DLN-60
< COMPONENT DIAGNOSIS >[ATX14B]
P1823 2-4 SOLENOID
Component Inspection
INFOID:0000000001737150
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer terminal cord assembly harness connector.
3. Check resistance between transfer terminal cord assembly ter- minals 4 and 5.
4. If the inspection results are abnormal replace the 2-4WD sole- noid. Refer to DLN-16, "
Component Parts Location".
4 - 5 : Approx. 22.8 - 25.2 Ω
WDIA0187E
Revision: March 2010
2008 QX56

P1824 TRANSFER MOTORDLN-61
< COMPONENT DIAGNOSIS > [ATX14B]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
P1824 TRANSFER MOTOR
DescriptionINFOID:0000000001737151
Motor does not operate properly due to open or short circuit in transfer motor or transfer motor relay.
DTC LogicINFOID:0000000001737152
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Perform self-diagnosis.
Is DTC P1824 displayed?
YES >> Perform diagnosis procedure. Refer to DLN-61, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000001737153
1.CHECK TRANSFER MOTOR RELAY SIGNAL
With CONSULT-III1. Start engine.
2. Select DATA MONITOR mode for ALL MODE AWD/4WD with CONSULT-III.
3. Read out the value of MOTOR RELAY and MOTOR RELAY MON.
DTC CONSULT-III Diagnostic item is detected when... Reference
[P1824] MOTOR RELAY Motor does not operate properly due to
open or short circuit in transfer motor or
transfer motor relay.Refer to DLN-61
.
Monitored
item Condition Display value
(Approx.)
MOTOR
RELAY • Accelerator ped-
al depressed
• Vehicle stopped
• Engine running
• Brake pedal de- pressed 4WD shift switch: 2WD OFF
4WD shift switch: AUTO or
4LO (A/T selector lever P or N
position)
OFF
(ON for approx.
2 sec. after
shifting to P and
N.)
4WD shift switch: AUTO or
4LO (Except for A/T selector
lever P or N position) ON
4WD shift switch: 4H (A/T se-
lector lever P position) OFF
(ON for approx.
2 sec. after
shifting to P.)
4WD shift switch: 4H (Except
for A/T selector lever P posi-
tion) ON
Revision: March 2010
2008 QX56