clutch INFINITI QX56 2010 Factory User Guide

4WD SYSTEMDLN-15
< FUNCTION DIAGNOSIS > [ATX14B]
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TRANSFER FLUID TEMPERATURE SENSOR
The transfer fluid temperature sensor detects the trans fer fluid temperature and sends a signal to the transfer
control unit.
TRANSFER MOTOR
• The transfer motor drives the sub-oil pump to provi de proper lubrication and oil pressure control when the
vehicle is at standstill, during low-speed operations or is being driven in reverse.
• The main oil pump is operated by the driving force of t he mainshaft. In other words, sufficient oil pressure
buildup does not occur when the vehicle is at standsti ll or during low-speed operations. While the vehicle is
being driven in reverse, the main oil pump rotates in the reverse direction. Therefore the main oil pump does
not discharge oil pressure. During any of the above vehi cle operations, the transfer motor drives the sub-oil
pump to compensate for insufficient oil pressure.
• The transfer motor operates as follows:
- The motor relay turns OFF in the 2WD mode.
- The motor relay operates as described in the table below in modes other than the 2WD mode.
• 4WD shift switch, transmission range switch, Neutral-4LO switch, vehicle speed sensor and throttle position
sensor are used in conjunction with the transfer motor.
Transfer Motor Relay Operation
*: After 2.5 seconds have elapsed.
CLUTCH PRESSURE SOLENOID VALVE
The clutch pressure solenoid valve distributes front and rear torque in AUTO mode.
2-4WD SHIFT SOLENOID VALVE
The 2-4WD shift solenoid valve operates to apply oil pressure to the wet-multiplate clutch, depending on the
drive mode. The driving force is transmitted to the front wheels through the clutch so the vehicle is set in the
4WD mode. Setting the vehicle in the 2WD mode requires no pressure buildup. In other words, pressure force
applied to the wet-multiplate clutch becomes zero.
TRANSFER CONTROL DEVICE
Integrates actuator motor and actuator position switch.
4WD shift switch A/T selector lever position Vehicle speed
(VSS) Accelerator pedal position Motor relay drive
command
2WD ———OFF
4H (LOCK) and 4LO N position
0— ON
P position 00 - 0.07/8
OFF*
0.07/8 - 1/8 HOLD
1/8 - MAX ON
Other than R position 0 < VSS ≤
50 km/h (31 MPH)
— ON
50 km/h (31 MPH) < VSS < 55 km/h (34 MPH) HOLD
55 km/h (34 MPH) ≤ VSS OFF
R position —— ON
R position —— ON
AUTO P or N position 0
0 - 0.07/8
OFF*
0.07/8 - 1/8 HOLD
1/8 - MAX ON
0 < VSS ≤ 50 km/h (31 MPH)
— ON
50 km/h (31 MPH) < VSS < 55 km/h (34 MPH) HOLD
55 km/h (34 MPH) ≤ VSS OFF
Other than R, P and N posi-
tion 0 < VSS ≤
50 km/h (31 MPH)
— ON
50 km/h (31 MPH) < VSS < 55 km/h (34 MPH) HOLD
55 km/h (34 MPH) ≤ VSS OFF
Revision: April 20092010 QX56

4WD SYSTEMDLN-17
< FUNCTION DIAGNOSIS > [ATX14B]
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CAN CommunicationINFOID:0000000005148773
Refer to LAN-14, "Trouble Diagnosis Flow Chart".
1. A: Transfer shut off relay E69
B: Transfer shift low relay E47
C: Transfer shift high relay E46 2. A: Actuator
B: Transfer control device F58
C: Actuator lever
D: Transfer case 3. Wait detection switch F59
(View with transfer case removed)
4. A: Clutch pressure switch B: Line pressure switch
C: Transfer fluid temperature sensor
D: 2-4WD shift solenoid valve
E: Clutch pressure solenoid valve
(View with contro l valve removed
from transfer case) 5. A: Neutral 4LO switch F60
B: ATP switch F55
C: Transfer motor F57
D: Transfer terminal cord assembly F56
E: Oil filter 6. Combination meter M23, M24
A: 4WD warning lamp
B: ATP warning lamp
C: 4LO indicator lamp (located in in-
formation display)
D: 4WD shift indicator lamp
7. 4WD shift switch M141 8. Transfer control unit E142, E143 9. A: Transfer dropping resistor E135
B: Transfer motor relay E153, E154
(View with battery removed)
Revision: April 20092010 QX56

DLN-20
< FUNCTION DIAGNOSIS >[ATX14B]
DIAGNOSIS SYSTEM (T
RANSFER CONTROL UNIT)
4L SW [On/Off] ×–×4WD shift switch status is displayed.
(4L means 4LO of 4WD shift switch.)
N POSI SW TF [On/Off] ×–×Neutral-4LO switch signal status is displayed.
ATP SWITCH [On/Off] ×–×ATP switch signal status is displayed.
WAIT DETCT SW [On/Off] ×–×Wait detection switch status is displayed.
LINE PRES SW [On/Off] ×–×Line pressure switch status is displayed.
CL PRES SW [On/Off] ×–×Clutch pressure switch status is displayed.
N POSI SW AT [On/Off] ×–×N position signal of transmission range switch
status is displayed.
Signal input with CAN communication line.
R POSI SW AT [On/Off] ×–×R position signal of transmission range switch
status is displayed.
Signal input with CAN communication line.
P POSI SW AT [On/Off] ×–×P position signal of transmission range switch
status is displayed.
Signal input with CAN communication line.
ABS OPER SW [On/Off] ×–×ABS operation signal status is displayed.
Signal input with CAN communication line.
VDC OPER SW [On/Off] ×–×VDC operation signal status is displayed.
Signal input with CAN communication line.
TCS OPER SW [On/Off] ×–×TCS operation signal status is displayed.
Signal input with CAN communication line.
THROTTLE POSI [0.0/8] –×× Thottle position status is displayed.
Signal input with CAN communication line.
4WD MODE [AUTO/LOCK/2WD/4L] – ××Control status of 4WD recognized by transfer
control unit. (AUTO, 4H, 2WD or 4LO)
VHCL/S COMP [km/h] or [mph] –×× Vehicle speed recognized by transfer control
unit.
COMP CL TORQ [kgm] –×× Calculated torque recognized by transfer con-
trol unit.
DUTY SOLENOID [%] –×× Control value of clutch pressure solenoid.
2-4WD SOL [On/Off] –×× Output condition to 2-4WD solenoid.
2-4WD SOL MON [On/Off] ––×Check signal for transfer control unit signal
output.
MOTOR RELAY [On/Off] –×× Transfer motor relay signal status is dis-
played.
MOTOR RELAY MON [On/Off] ––×Check signal for transfer control unit signal
ou
t

put.
4WD FAIL LAMP [On/Off] –×× Control status of 4WD warning lamp is dis-
played.
2WD IND [On/Off] ––×Control status of 4WD shift indicator lamp
(2WD indicator lamp) is displayed.
AUTO IND [On/Off] ––×Control status of 4WD shift indicator lamp
(2WD and AUTO indicator lamp) is displayed.
LOCK IND [On/Off] ––×Control status of 4WD shift indicator lamp
(2WD, AUTO and Lock indicator) is displayed.
4L IND [On/Off] ––×Control status of 4LO indicator lamp is dis-
played.
Monitored item (Unit)
Monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELEC-
TION FROM
MENU
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DIAGNOSIS SYSTEM (TRANSFER CONTROL UNIT)DLN-21
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WORK SUPPORT
When there is no malfunction with transfer and 4WD sys tem, the following symptoms in AUTO mode may be
claimed by a customer: vibration when accelerating on a low µ road (snow-covered or icy road) or a slight
shock is felt at a few hertz as if it were being pushed lightly from behind.
It is possible to deal with these symptoms by changing the CLUTCH FORCE RELEASE LIMIT VALUE. How-
ever, be careful when changing the value because it may adversely affect driving performance.
Operation Procedure
1. Connect CONSULT-III.
2. Touch WORK SUPPORT.
3. Select from CLUTCH/F RLS LIM ADJ, screen of data monitor mode is displayed.
Clutch Force Release Limit Adjustment
1. Initial CLUTCH FORCE RELEASE LIMIT value 0.3 kgm appears under CONDITION SETTING on CON-
SULT-III display.
2. Touch 1.2 on the display.
3. Display changes to NOW ADJUSTING in a short time.
4. When clutch force release limit value is set to 1.2 kgm, current value 0.3 kgm shown on display will be replaced by 1.2 kgm and ADJUSTME NT COMPLETE will appear at the same time. Clutch force release
limit value setting is now complete.
ATP IND [On/Off] ––×Control status of ATP warning lamp is dis-
played.
SHIFT POS SW1 [On/Off] ×–×Actuator position switch 1 (Low) signal status
is displayed.
SHIFT POS SW2 [On/Off] ×–×Actuator position switch 2 (high) signal status
is displayed.
SHIFT ACT1 [On/Off] –×× Output condition to actuator motor (clockwise)
SHIFT AC MON1 [On/Off] ×–×Check signal for transfer control unit signal
output
SHIFT ACT2 [On/Off] –×× Output condition to actuator motor (counter-
clockwise)
SHIFT AC MON2 [On/Off] ×–×Check signal for transfer control unit signal
output
T/F F SPEED [km/h] or [mph] ×–×Displayed, but do not use.
A/T R SPEED [km/h] or [mph] ×–×Output shaft revolution signal (output speed
sensor) calculated by TCM.
Signal input with CAN communication line.
AT GEAR POSI [1/2/3/4/5] ×–×A/T actual gear position is displayed.
Monitored item (Unit)
Monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELEC-
TION FROM
MENU
1.2 kg-m : Tight corner braking symptom is alleviated. However, vibration may occur when acceler-
ating on a low µ road (icy road, etc.).
0.3 kg-m : Initial set value.
0.2 kg-m : Do not set to th is value because the tight
corner braking symptom will get worse.
Revision: April 20092010 QX56

DLN-54
< COMPONENT DIAGNOSIS >[ATX14B]
P1822 CLUTCH PRESSURE SOLENOID
P1822 CLUTCH PRESSURE SOLENOID
DescriptionINFOID:0000000005148817
Proper voltage is not applied to the clutch pres
sure solenoid valve due to open or short circuit.
DTC LogicINFOID:0000000005148818
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Perform self-diagnosis.
Is DTC P1822 displayed?
YES >> Perform diagnosis procedure. Refer to DLN-54, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000005148819
Regarding Wiring Diagram information, refer to DLN-89, "Wiring Diagram - ALL-MODE 4WD SYSTEM -".
1.CHECK CLUTCH PRESSURE 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 DUTY SOLENOID.
Without CONSULT-III1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
DTC CONSULT-III Diagnostic item is detected when... Reference
[P1822] DUTY SOLENOID Proper voltage is not applied to clutch
pressure solenoid valve due to open or
short circuit.Refer to
DLN-54
.
Condition Display value
• Vehicle stopped
• Engine running
• A/T selector lever N position
• Brake pedal depressed 4WD shift switch: 2WD
4%
4WD shift switch: AUTO 96 - 4%
4WD shift switch: 4H or
4LO 4%
SDIA2719E
Revision: April 20092010 QX56

P1822 CLUTCH PRESSURE SOLENOIDDLN-55
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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, tr ansfer 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 TRAN SFER CONTROL UNIT AND TRANSFER DROPPING RESISTOR
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connecto r and transfer dropping resistor harness connector.
Connector TerminalConditionVoltage
(Approx.)
E142 10 -
Ground • Vehicle stopped
• Engine running
• A/T selector lever
N position
• Brake pedal de- pressed 4WD shift switch:
AUTO
4 - 14V
4WD shift switch:
2WD, 4H or 4LO Less than
1V
19 -
Ground • Vehicle stopped
• Engine running
• A/T selector lever
N position
• Brake pedal de-
pressed 4WD shift switch:
AUTO
1.5 - 3V
4WD shift switch:
2WD, 4H or 4LO Less than
1V
Continuity should exist.
SDIA2720E
Continuity should exist.
SDIA2721E
Revision: April 20092010 QX56

DLN-56
< COMPONENT DIAGNOSIS >[ATX14B]
P1822 CLUTCH PRESSURE SOLENOID
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.
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-81, "
Reference Value".
Continuity should exist.
SDIA2722E
Continuity should exist.
SDIA2723E
6 - 19 : Approx. 3.0 - 3.4
Ω
SDIA2724E
1 - 2 : Approx. 11.2 - 12.8 Ω
SDIA2725E
Revision: April 20092010 QX56

P1822 CLUTCH PRESSURE SOLENOIDDLN-57
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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-130, "
Removal and Installation".
Component InspectionINFOID:0000000005148820
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 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: April 20092010 QX56

P1827 CLUTCH PRESSURE SWITCHDLN-71
< COMPONENT DIAGNOSIS > [ATX14B]
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P1827 CLUTCH PRESSURE SWITCH
DescriptionINFOID:0000000005148833
Improper signal from the clutch pressure switch is input due to open or short circuit. Also, a malfunction may
have occured in clutch pressure switch or hydraulic circuit.
DTC LogicINFOID:0000000005148834
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Perform self-diagnosis.
Is DTC P1827 displayed?
YES >> Perform diagnosis procedure. Refer to DLN-71, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis ProcedureINFOID:0000000005148835
Regarding Wiring Diagram information, refer to DLN-89, "Wiring Diagram - ALL-MODE 4WD SYSTEM -".
1.CHECK CLUTCH PRESSURE SWITCH SIGNAL
With CONSULT-III1. Start engine.
2. Select DATA MONITOR mode for ALL MODE AWD/4WD with CONSULT-III.
3. Read out ON/OFF switching action of the CL PRES SW while operating 4WD shift switch.
Without CONSULT-III
1. Start engine.
DTCCONSULT-III Diagnostic item is detected when... Reference
[P1827] CLUTCH PRES SW • Improper signal from clutch pressure
switch is input due to open or short cir-
cuit.
• Malfunction occurs in clutch pressure switch or hydraulic circuit. Refer to DLN-71
.
Condition
Display value
• Ignition switch: ON
• A/T selector lever D posi- tion 4WD shift switch: AUTO or 4H (Wait
function is not operating.)
ON
Ignition switch: ON 4WD shift switch: 2WD (Wait func-
tion is not operating.) OFF
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DLN-72
< COMPONENT DIAGNOSIS >[ATX14B]
P1827 CLUTCH PRESSURE SWITCH
2. Check voltage between transfer control unit harness connector
terminals and ground.
Are inspection results normal?
YES >> GO TO 5.
NO >> GO TO 2.
2.CHECK HARNESS BETWEEN TRANSFER CONT ROL UNIT AND CLUTCH PRESSURE SWITCH
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the transfer terminal cord assembly harness con-
nector.
3. Check continuity between transfer control unit harness connec- tor E143 terminal 34 and transfer terminal cord assembly har-
ness connector F56 terminal 7
Also check harness for short to ground and short to power.
Are inspection results normal?
YES >> GO TO 3.
NO >> Repair or replace damaged parts.
3.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to DLN-81, "
Reference Value".
Are inspection results normal?
YES >> GO TO 4.
NO >> Check transfer control unit pin terminals for damage or loose connection with the harness connec- tor. If any items are damaged, repair or replace damaged parts.
4.CHECK CLUTCH PRESSURE SWITCH
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Remove clutch pressure switch. Refer to DLN-16, "
Component Parts Location".
3. Push and release clutch pressure switch and check continuity between terminal 7 and ground.
Are inspection results normal?
YES >> GO TO 5.
NO >> Replace clutch pressure switch.
5.CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
Are inspection results normal?
Connector Terminal ConditionVoltage
(Approx.)
E143 34 -
Ground • Ignition switch: ON
• A/T selector lever D
position 4WD shift switch:
AUTO or 4H (Wait
function is not op-
erating.)
0V
Ignition switch: ON 4WD shift switch:
2WD (Wait function
is not operating.)Battery
voltage
SDIA2746E
Continuity should exist.
SDIA2747E
Terminal
Condition Continuity
7 -
Ground Push clutch pressure switch
Yes
Release clutch pressure switch No
WDIA0171E
Revision: April 20092010 QX56