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![INFINITI QX56 2004 Factory Service Manual ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
TF-37
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*: This item is indicated as “COMP CL TORQ”.Clutch limit [N·m (kg-m, ft.-lb.)]Clutch force re INFINITI QX56 2004 Factory Service Manual ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
TF-37
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*: This item is indicated as “COMP CL TORQ”.Clutch limit [N·m (kg-m, ft.-lb.)]Clutch force re](/manual-img/42/57034/w960_57034-3161.png)
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
TF-37
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*: This item is indicated as “COMP CL TORQ”.Clutch limit [N·m (kg-m, ft.-lb.)]Clutch force release limit value set in
WORK SUPPORT
Voltage [V]Value measured by voltage probe is dis-
played.
Frequency [Hz]Value measured by pulse probe is dis-
played. If measurement is impossible, “#”
sign is displayed. “#” sign is also displayed
at the final data value until the measure-
ment result is obtained.
DUTY-HI
Duty cycle value for measurement probe is
displayed.
DUTY-LOW
PLS WIDTH-HI
Measured pulse width of measurement
probe is displayed.
PLS WIDTH-LOW
FR/RR G-SEN [G] Displayed, but do not use.
TF F SPEED [km/h], [MPH] Displayed, but do not use.
AT R SPEED [km/h], [MPH] Indicates A/T rear vehicle speed.
A/T actual gear position Indicates A/T actual gear position.
VDC OPER SW [ON-OFF] Indicates VDC operation switch.
TCS OPER SW [ON-OFF] Indicates TCS operation switch.
AT P L A M P [O N - O F F ]Indicates C/U control signal output of ATP
lamp. Item [Unit]Monitor item
Remarks ECU
INPUT
SIGNALSMAIN
SIGNALSSELEC-
TION
FROM
MENU
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TF-38
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Revision: August 20072004 QX56
REFERENCE VALUE IN DATA MONITOR MODE
Indicated items
(Screen terms for CONSULT-II, “DATA
MONITOR” mode)Display Conditions
Throttle position sensor
(THRTL POS SEN) 0.0/8 - 8.0/8 Throttle valve fully closed to fully open
Transfer fluid temperature sensor
(FLUID TEMP SE)Approx. 1.5 - 0.5V Transfer fluid temperature approx. 20 - 80°C (68 - 176°F)
ABS operation switch
(ABS OPER SW)OFF ABS is not operating.
ON ABS is operating.
2WD position
(2WD SWITCH)ON 4WD shift switch is in “2WD”.
OFF Except the above condition
Lock position
(LOCK SWITCH)ON 4WD shift switch is in “4H”.
OFF Except the above condition
Neutral-4LO switch
(N POSI SW TF)
AT P s w i tc h
(ATP SWITCH)
Wait detection switch
(WAIT DETCT SW)4WD shift switch position2WD,
AUTO, 4H(N) 4LO
AT P s w i t c h O F F O N O F F
Neutral-4LO switch/Wait detec-
tion switch See Note.OFF ON
Note: When shifting into or out of “4LO” the switches turn ON when “Wait” function is oper-
ating and they turn OFF when “Wait” function is canceled.
Tran s fe r mo to r re lay
(MOTOR RELAY)
Transfer motor relay monitor
(MOTOR RELAY MON)Throttle valve4WD
shift
switchA/T selector
leverMotor relay/
Motor relay
monRemarks
Fully closed2WD — OFF —
AUTO,
4LOP, N O F F
ON for approx. 2 sec. after
shifting to “P” and “N”
Others ON
4HPOFF
ON for approx. 2 sec. after
shifting to “P”
Others ON
Line pressure switch
(LINE PRES SW)OFFThe vehicle has been left at room temperature for 5 min-
utes and more with ignition switch in “OFF” position.
ONIgnition switch in “ON”, and 4WD shift switch in “AUTO” or
“4H” and A/T selector lever in “D”.
Clutch pressure switch
(CL PRES SW)OFFIgnition switch in “ON”, and 4WD shift switch in “2WD”.
(“Wait” function is not operating.)
ONIgnition switch in “ON”, and 4WD shift switch in “AUTO” or
“4H” and A/T selector lever in “D”. (“Wait” function is not
operating.)
Vehicle speed
(VHCL/S COMP)0 km/h (0 MPH) — —
Control torque
(COMP CL TORQ)0 kg-m
4WD shift switch
(“Wait” function is not oper-
ating.)In “2WD” position
39 - 1,353 N·m
(4 - 138 kg-m, 29 - 998 ft.-lb.)In “AUTO” position
1,353 N·m
(138 kg-m, 998 ft.-lb.)In “4H” or “4LO” position
4WD solenoid
(DUTY SOLENOID)4% In “2WD” position
96 - 4% In “AUTO” position
4% In “4H” or “4LO” position
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
TF-41
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WORK SUPPORT
Purpose
When there is no problem with transfer and 4WD system, the following symptom in “AUTO” mode may be
claimed by a customer.
Vibration when accelerating on snow-covered or icy roads. (Note)
AUTO indicator lamp
(AUTO IND)OFFEngine at rest during 2WD-mode operation or system out
of order
ON 4WD shift switch in “4LO” or “4H” or “AUTO” position
LOCK indicator lamp
(LOCK IND)OFFEngine at rest and 4WD shift switch in “AUTO” position
during 2WD-mode operation or system out of order
ON 4WD shift switch in “4H” or “4LO” position
4LO indicator lamp
(4L IND)OFFEngine at rest and 4WD shift switch in “AUTO” position
during 2WD-mode operation or system out of order
ON 4WD shift switch in “4LO” position
Clutch force release limit
(CL/F RLS LIM)0.2, 0.3, 1.2 kgmIndicates the clutch force release setting applied using the
scan tool. 0.3 kgm is the default setting.
VDC operation switch
(VDC OPER SW)OFF VDC is not operating.
ON VDC is operating.
TCS operation switch
(TCS OPER SW)OFF TCS is not operating.
ON TCS is operating.
ATP indicator lamp
(ATP IND)OFF Normal operation.
ONDriver is attempting to shift into or out of 4L while the AT is
not in neutral.
Transfer case F speed
(T/F F SPEED)0.0 km/h (0.0 MPH) —
Automatic transmission R speed
(AT R SPEED)0.0 km/h (0.0 MPH) —
Automatic transmission gear position
(AT GEAR POSI)1,2,3,4 Displays actual AT gear position. Indicated items
(Screen terms for CONSULT-II, “DATA
MONITOR” mode)Display Conditions
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TF-42
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Revision: August 20072004 QX56
It is possible to deal with these symptoms by changing “CLUTCH FORCE RELEASE LIMIT VALUE”.
However, be careful when changing the values because it may adversely affect driving performance.
NOTE:
A slight shock is felt at a few hertz as if it were being pushed lightly from behind.
CONSULT-II Setting Procedure
1. Turn ignition switch to “OFF” position.
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CON-
VERTER, malfunctions might be detected in self-diagnosis
depending on control unit which carry out CAN communication.
2. Connect CONSULT-II and CONSULT-II CONVERTER to data
link connector.
3. Turn ignition switch to “ON” position.
4. Touch “START (NISSAN BASED VHCL)”.
5. Touch “ALL MODE AWD/4WD”.
If "ALL MODE AWD/4WD" is not indicated, refer to GI-39,
"CONSULT-II Data Link Connector (DLC) Circuit" .
6. Touch “WORK SUPPORT”.
7. Select WORK ITEM by touching “CLUTCH/F RLS LIM ADJ”.
CLUTCH FORCE RELEASE LIMIT ADJUSTMENT
1.2 kg-m: Tight corner braking symptom is alleviated. However, vibration may occur when accelerating on a
low µ road (icy road, etc.).
0.3 kg-m: Initial set value
0.2 kg-m: Do not set to this value because the tight corner braking symptom will get worse.
1. Current CLUTCH FORCE RELEASE LIMIT value “0.3 kgm”
appears under “CONDITION SETTING” on CONSULT-II display.
2. Touch “1.2” on the display.
BCIA0029E
BCIA0031E
WDIA0085E
SMT968D
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ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
TF-43
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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 “ADJUSTMENT COMPLETE” will appear at the same time.
Clutch force release limit value setting is now complete.
SMT969D
SMT970D
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TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
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30Power supply for A/D
converter &Ignition key is set to ON position. 4.5 - 5.5V
Ignition key is set to OFF position. 0V
31Transfer fluid tempera-
ture sensor &At 20°C (68°F) 1.1V
At 80°C (176°F) 0.3V
33 Transfer shift relay (High)
&While actuator is operating from “4H”
to “4LO”Battery voltage
Actuator does not operate. 0V
34 Clutch pressure switch4WD shift switch is set to AUTO or
4H, then A/T selector lever is set to D
position. (wait detection system:
OFF)Battery voltage
4WD shift switch is set to 2WD,
AUTO or 4H, then A/T selector lever
is set to D position. (wait detection
system: ON)0V
35 Line pressure switch4WD shift switch is set to 2WD,
AUTO or 4H, then A/T selector lever
is set to D position.Battery voltage
—0V
36 CONSULT-II (RX) — — —
40 ATP switch
&A/T selector lever is set to P position. Battery voltage
A/T selector lever is set to any posi-
tion other than P.Less than 1V
41Transfer motor relay
monitorTransfer motor relay is ON. Battery voltage
Transfer motor relay is OFF. Less than 1V
42Transfer shift relay
(LOW)While actuator is operating from
“4LO” to “4H” positionBattery voltage
Actuator does not operate. 0V
43 Wait detection switch4WD shift switch is set to any posi-
tion other than 4LO.Battery voltage
4WD shift switch is set to 4LO posi-
tion.*3Less than 1V
44Transfer 4LO actuator
switch4WD shift switch is set to any posi-
tion other than 4LO. (Actuator: High
position)Battery voltage
4WD shift switch is set to 4LO posi-
tion. (Actuator: Low position)Less than 1V
45 Ground — — — Te r m i n a l
No.Item ConditionJudgement standard
(Approx.)
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TF-60
4WD SOLENOID VALVE
Revision: August 20072004 QX56
4WD SOLENOID VALVEPFP:00000
Diagnostic ProcedureEDS00183
1. CHECK 4WD SOLENOID VALVE
Refer to TF-95, "
4WD SOLENOID VALVE, CLUTCH PRESSURE
SWITCH AND LINE PRESSURE SWITCH" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace 4WD solenoid valve.
2. CHECK POWER SOURCE CIRCUIT
1. Turn ignition switch to OFF position.
2. Disconnect transfer control unit harness connector E142.
3. Check resistance between transfer terminal cord assembly har-
ness connector F56 terminal 6 (L) and transfer control unit har-
ness connector E142 terminal 10 (L/W).
OK or NG
OK >> GO TO 3.
NG >> Check the following.
Transfer dropping resistor
Refer to TF-96, "
TRANSFER DROPPING RESISTOR" .
Continuity between transfer terminal cord assembly harness connector F56 terminal 6 (L) and
transfer dropping resistor harness connector E135 terminal 2 (L).
Continuity between transfer dropping resistor harness connector E135 terminal 1 (L/W) and
transfer control unit harness connector E142 terminal 10 (L/W).
3. CHECK POWER SOURCE CIRCUIT
1. Turn ignition switch to OFF position.
2. Check continuity between transfer terminal cord assembly har-
ness connector F56 terminal 6 (L) and transfer control unit har-
ness connector E142 terminal 19 (L).
Continuity should exist.
OK or NG
OK >> GO TO 4.
NG >> Repair or replace harness between transfer terminal
cord assembly harness connector F56 terminal 6 (L)
and transfer control unit harness connector E142 termi-
nal 19 (L).
SMT775D
Resistance : 11.2 - 12.8Ω
LDIA0067E
LDIA0068E
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TF-72
CLUTCH PRESSURE SWITCH
Revision: August 20072004 QX56
CLUTCH PRESSURE SWITCHPFP:00000
Diagnostic ProcedureEDS00188
1. CHECK MALFUNCTION
Is this malfunction detected only while driving in reverse?
Ye s o r N o
Yes >> Check A/T PNP switch "R" position.
Refer to AT-109, "DTC P0705 PARK/NEUTRAL POSITION SWITCH" .
No >> GO TO 2.
2. CHECK OTHER MALFUNCTION
Are other malfunctions also detected by self-diagnosis and CONSULT-II?
Refer to TF-27, "
Trouble Diagnosis without CONSULT-II" and TF-31, "Trouble Diagnosis with CONSULT-II" .
Ye s o r N o
Yes >> Check for other malfunctions.
(When other malfunctions are eliminated, clutch pressure switch malfunction display may dis-
appear.)
No >> GO TO 3.
3. CHECK 2-4WD SHIFT SOLENOID VALVE AND 4WD SHIFT SWITCH CIRCUITS
Check 2-4WD shift solenoid valve and 4WD shift switch circuits.
OK or NG
OK >> GO TO 4.
NG >> Check, repair or replace faulty parts.
4. CHECK INPUT SIGNAL
Do you have CONSULT-II?
Ye s o r N o ?
Yes >> GO TO 5.
No >> GO TO 6.