display INFINITI QX4 2005 Factory Service Manual

TROUBLE DIAGNOSIS
TF-49
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Revision: October 20052005 QX56
WORK SUPPORT
When there is no problem with transfer and 4WD system, following symptom in “AUTO” mode may be claimed
by a customer.

Vibration when accelerating on a low µ road (snow-covered or icy road)
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.
Operation Procedure
1. Perform “CONSULT-II SETTING PROCEDURE”. Refer to TF-44, "CONSULT-II SETTING PROCEDURE"
.
2. Touch “WORK SUPPORT”.
3. Select from “CLUTCH/F RLS LIM ADJ”, screen of data monitor mode is displayed.
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 (Revolution
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.
Voltage [V] – –×The value measured by the voltage probe is
displayed.
Frequency [Hz] – –×
The value measured by the pulse probe is
displayed. DUTY-HI (high) [%] – –×
DUTY-LOW (low) [%] – –×
PLS WIDTH-HI [msec] – –×
PLS WIDTH-LOW [msec] – –× Monitored item (Unit)Monitor item selection
Remarks
ECU INPUT
SIGNALSMAIN
SIGNALSSELEC-
TION FROM
MENU

TF-50
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
Clutch Force Release Limit Adjustment
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.
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.
Self-diagnostic ProcedureEDS002HL
SELF-DIAGNOSTIC PROCEDURE (WITH CONSULT-II)
Refer to TF-45, "SELF-DIAG RESULT MODE" .
SELF-DIAGNOSTIC PROCEDURE (WITHOUT CONSULT-II)
Description
If the engine starts when there is something wrong with the 4WD system, the 4WD warning lamp turns ON or
flickers in the combination meter. When the system functions properly, the warning lamp turns ON when the
ignition switch is turned to “ON”, and it turns OFF after engine starts. To locate the cause of a problem, start
the self-diagnosis function. The 4WD warning lamp in the combination meter will indicate the problem area by
flickering according to the self-diagnostic results. As for the details of the 4WD warning lamp flickering pat-
terns, refer to TF-51, "
Diagnostic Procedure" . 1.2 kg-m : Tight corner braking symptom is allevi-
ated. 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.
SMT968D
SMT969D
SMT970D

TROUBLE DIAGNOSIS
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CAUTION:

If “CAN communication” is displayed with other DTCs, first perform the trouble diagnosis for CAN communication line.

If “ABS operation signal”, “VDC operation signal" or “TCS operation signal" is displayed, first perform the trouble diag-
nosis for ABS system.

If “Output shaft revolution signal” is displayed, first perform the trouble diagnosis for A/T system.
NOTE:

If "actuator position switch" or “actuator circuit” is displayed, first erase self-diagnostic results. ("Actuator position switch" or “actua-
tor circuit” may be displayed after installing transfer control unit or transfer assembly.)

If “clutch pressure switch” or “line pressure switch” is displayed only while driving in reverse, check the continuity of “R” position on
A/T PNP switch. When there is nothing wrong with the electrical system, check the hydraulic system.
ERASE SELF-DIAGNOSIS

In order to make it easier to find the cause of hard-to-duplicate malfunctions, malfunction information is
stored into the control unit as necessary during use by the user. This memory is not erased no matter how
many times the ignition switch is turned ON and OFF.

However, this information is erased by turning ignition switch “OFF” after performing self-diagnostics or by
erasing the memory using the CONSULT-II.
24PNP switch signal
(from TCM)
When A/T PNP switch signal is malfunctioning or com-
munication error between the vehicles.TF-69, "PNP Switch
Signal (TCM)"
Repeats flickering
every 2 to 5 sec.— Circuits that the self-diagnosis covers have no malfunction. —
Repeats flickering
every 0.25 sec.Data erase display

Power supply failure of memory back-up.

Battery performance is poor.TF-54, "
Power Supply
Circuit For Transfer
Control Unit"
No flickeringPNP switch or 4WD
shift switch
PNP switch or 4WD shift switch circuit is shorted or
open.TF-69, "PNP Switch
Signal (TCM)", TF-62,
"4WD Shift Switch"
Flickering pattern or
flickering conditionItems Malfunction Check items

TF-54
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: October 20052005 QX56
TROUBLE DIAGNOSIS FOR SYSTEMPFP:00000
Power Supply Circuit For Transfer Control UnitEDS0 02 I4
CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE
Data are reference value.
TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE
Data are reference value and are measured between each terminal and ground.
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.Monitored item [Unit] Content Condition Display value
BATTERY VOLT [V]Power supply voltage for
transfer control unitIgnition switch: ON Battery voltage
Te r m i n a lWire
colorItem Condition Data (Approx.)
3 B Ground Always 0V
6 B Ground Always 0V
16 Y/R Power supplyIgnition switch: ON Battery voltage
Ignition switch: OFF 0V
22 Y/R Power supplyIgnition switch: ON Battery voltage
Ignition switch: OFF 0V
29 L/W Ignition switch monitorIgnition switch: ON Battery voltage
Ignition switch: OFF 0V
30 SB Shut off relayIgnition switch: ON 0V
Ignition switch: OFF Battery voltage
45 B Ground Always 0V
47 WPower supply
(Memory back-up)Ignition switch: ON Battery voltage
Ignition switch: OFF Battery voltage

TROUBLE DIAGNOSIS FOR SYSTEM
TF-57
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Revision: October 20052005 QX56
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer shut off relay. Refer to TF-22, "
Location of Electrical Parts" .
3. Apply 12V direct current between transfer shut off relay termi-
nals 1 and 2.
4. Check continuity between relay terminals 3 and 5.
5. If NG, replace the transfer shut off relay. Refer to TF-22, "
Loca-
tion of Electrical Parts" .
Transfer Control UnitEDS002I5
DIAGNOSTIC PROCEDURE
1. INSPECTION START
Do you have CONSULT-II?
YES or NO
YES >> GO TO 2.
NO >> GO TO 3.
2. PERFORM SELF-DIAGNOSIS (WITH CONSULT-II)
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “SELF-DIAG RESULTS” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Touch “ERASE”.
4. Turn ignition switch “OFF” and wait at least 10 seconds.
5. Perform the self-diagnosis again.
Is the
“CONTROL UNIT 1 [P1802]”, “CONTROL UNIT 2 [P1803]”, “CONTROL UNIT 3 [P1804]” or “CONTROL
UNIT 4 [P1809]” displayed?
YES >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
NO >> Inspection End.
3. PERFORM SELF-DIAGNOSIS (WITHOUT CONSULT-II)
Without CONSULT-II
1. Perform the self-diagnosis and then erase self-diagnostic results. Refer to TF-50, "
SELF-DIAGNOSTIC
PROCEDURE (WITHOUT CONSULT-II)" and TF-53, "ERASE SELF-DIAGNOSIS" .
2. Perform the self-diagnosis again.
Do the self-diagnostic results indicate AD converter?
YES >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
NO >> Inspection End.
Condition Continuity
12V direct current supply between terminals 1 and 2 Yes
OFF No
SCIA1245E

TROUBLE DIAGNOSIS FOR SYSTEM
TF-59
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Revision: October 20052005 QX56
Neutral-4LO SwitchEDS002I8
CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE
Data are reference value.
TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE
Data are reference value and are measured between each terminal and ground.
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.Monitored item Content Condition Display value
N POSI SW TF [ON/
OFF]Condition of neutral-4LO
switch

Vehicle stopped

Engine running

A/T selector lever “N”
position

Brake pedal depressed4WD shift switch: 2WD,
AUTO or 4HOFF
4WD shift switch: 4H to
4LO (While actuator
motor is operating.)OFF → ON
4WD shift switch: 4LO to
4H (While actuator motor
is operating.)ON → OFF
4WD shift switch: 4LO ON
Te r m i n a lWire
colorItem Condition Data (Approx.)
25 V Neutral-4LO switch

Vehicle stopped

Engine running

A/T selector
lever “N” position

Brake pedal
depressed4WD shift switch: 2WD, AUTO or 4H Battery voltage
4WD shift switch: 4H to 4LO (While actua-
tor motor is operating.)Battery volt-
age → 0V
4WD shift switch: 4LO to 4H (While actua-
tor motor is operating.)0V → Battery
voltage
4WD shift switch: 4LO 0V

TF-60
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: October 20052005 QX56
DIAGNOSTIC PROCEDURE
1. CHECK 4LO POSITION SWITCH SIGNAL
With CONSULT-II
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “N POSI SW TF”.
Without CONSULT-II
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND NEUTRAL-4LO SWITCH
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the neutral-4LO switch harness connector.
3. Check continuity between transfer control unit harness connec-
tor E143 terminal 25 (V) and neutral-4LO switch harness con-
nector F60 terminal 13 (V).
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
Condition Display value

Vehicle stopped

Engine running

A/T selector lever “N” position

Brake pedal depressed4WD shift switch: 2WD,
AUTO or 4HOFF
4WD shift switch: 4H to
4LO (While actuator
motor is operating.)OFF → ON
4WD shift switch: 4LO to
4H (While actuator motor
is operating.)ON → OFF
4WD shift switch: 4LO ON
SDIA2692E
ConnectorTe r m i n a l
(Wire
color)ConditionVoltage
(Approx.)
E143 25 (V) -
Ground

Vehicle stopped

Engine running

A/T selector lever
“N” position

Brake pedal
depressed4WD shift switch:
2WD, AUTO or 4HBattery
voltage
4WD shift switch: 4H
to 4LO (While actuator
motor is operating.)Battery
voltage
→ 0V
4WD shift switch: 4LO
to 4H (While actuator
motor is operating.)0V →
Battery
voltage
4WD shift switch: 4LO 0V
SDIA2693E
Continuity should exist.
SDIA2694E

TF-62
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: October 20052005 QX56
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect neutral-4LO switch harness connector.
3. Remove neutral-4LO switch. Refer to TF-22, "
Location of Electrical Parts" .
4. Push and release neutral-4LO switch and check continuity
between neutral-4LO switch terminals 12 and 13.
5. If NG, replace the neutral-4LO switch. Refer to TF-22, "
Location
of Electrical Parts" .
4WD Shift SwitchEDS0 02 I9
CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE
Data are reference value.
TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE
Data are reference value and are measured between each terminal and ground.
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.Terminal Condition Continuity
12 - 13Push neutral-4LO switch Yes
Release neutral-4LO switch No
SDIA2696E
Monitored item [Unit] Content Condition Display value
2WD SWITCH [ON/
OFF]Input condition from 4WD
shift switch4WD shift switch: 2WD ON
4WD shift switch: AUTO, 4H or 4LO OFF
AUTO SWITCH [ON/
OFF]Input condition from 4WD
shift switch4WD shift switch: AUTO ON
4WD shift switch: 2WD, 4H or 4LO OFF
LOCK SWITCH [ON/
OFF]Input condition from 4WD
shift switch4WD shift switch: 4H ON
4WD shift switch: 2WD, AUTO or 4LO OFF
4L SWITCH [ON/OFF]Input condition from 4WD
shift switch4WD shift switch: 4LO ON
4WD shift switch: 2WD, AUTO or 4H OFF
4WD MODE [AUTO/
LOCK/2WD/4L]Control status of 4WD
(Output condition of 4WD
shift indicator lamp and
4LO indicator lamp)

Vehicle stopped

Engine running

A/T selector lever “N”
position

Brake pedal depressed4WD shift switch: 2WD 2WD
4WD shift switch: AUTO AUTO
4WD shift switch: 4H LOCK
4WD shift switch: 4LO 4L
Te r m i n a lWire
colorItem Condition Data (Approx.)
9G/W4WD shift switch
(2WD)Ignition switch: ON4WD shift switch: 2WD Battery voltage
4WD shift switch: AUTO, 4H or 4LO 0V
18 O4WD shift switch
(4H)Ignition switch: ON4WD shift switch: 4H Battery voltage
4WD shift switch: 2WD, AUTO or 4LO 0V
23 R4WD shift switch
(4LO)Ignition switch: ON4WD shift switch: 4LO Battery voltage
4WD shift switch: 2WD, AUTO or 4H 0V
24 LG/R4WD shift switch
(AUTO)Ignition switch: ON4WD shift switch: AUTO Battery voltage
4WD shift switch: 2WD, 4H or 4LO 0V

TF-66
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: October 20052005 QX56
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 second.)
2. Disconnect 4WD shift switch harness connector.
3. Operate 4WD shift switch and check continuity between 4WD
shift switch terminals.
4. If NG, replace the 4WD shift switch.
Wait Detection SwitchEDS002IA
CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE
Data are reference value.
TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE
Data are reference value and are measured between each terminal and ground.
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.Connector Terminal Condition Continuity
M1411 - 24WD shift switch: 2WD Yes
4WD shift switch: AUTO, 4H and
4LONo
1 - 34WD shift switch: AUTO Yes
4WD shift switch: 2WD, 4H and
4LONo
1 - 44WD shift switch: 2WD No
4WD shift switch: AUTO, 4H and
4LOYe s
1 - 54WD shift switch: 4H Yes
4WD shift switch: 2WD, AUTO,
and 4LONo
1 - 64WD shift switch: 4LO Yes
4WD shift switch: 2WD, AUTO
and 4HNo
WDIA0205E
Monitored item Content Condition Display value
WAIT DETCT SW [ON/
OFF]Condition of wait detection
switch

Vehicle stopped

Engine running

A/T selector lever “N”
position

Brake pedal depressed4WD shift switch: 2WD,
AUTO or 4HOFF
4WD shift switch: 4H to
4LO (While actuator
motor is operating.)OFF → ON
4WD shift switch: 4LO to
4H (While actuator motor
is operating.)ON → OFF
4WD shift switch: 4LO ON
Te r m i n a lWire
colorItem Condition Data (Approx.)
43 G/Y Wait detection switch

Vehicle stopped

Engine running

A/T selector
lever “N” position

Brake pedal
depressed4WD shift switch: 2WD, AUTO or 4H Battery voltage
4WD shift switch: 4H to 4LO (While actua-
tor motor is operating.)Battery volt-
age → 0V
4WD shift switch: 4LO to 4H (While actua-
tor motor is operating.)0V → Battery
voltage
4WD shift switch: 4LO 0V

TROUBLE DIAGNOSIS FOR SYSTEM
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DIAGNOSTIC PROCEDURE
1. CHECK WAIT DETECTION SWITCH SIGNAL
With CONSULT-II
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “WAIT DETCT SW”.
Without CONSULT-II
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND WAIT DETECTION SWITCH
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the wait detection switch harness connector.
3. Check continuity between transfer control unit harness connec-
tor E143 terminal 43 (G/Y) and wait detection switch harness
connector F59 terminal 10 (G/Y).
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
Condition Display value

Vehicle stopped

Engine running

A/T selector lever “N” position

Brake pedal depressed4WD shift switch: 2WD, AUTO
or 4HOFF
4WD shift switch: 4H to 4LO
(While actuator motor is operat-
ing.)OFF → ON
4WD shift switch: 4LO to 4H
(While actuator motor is operat-
ing.)ON → OFF
4WD shift switch: 4LO ON
PDIA0221E
ConnectorTe r m i n a l
(Wire
color)ConditionVoltage
(Approx.)
E14343 (G/Y)
- Ground

Vehicle stopped

Engine running

A/T selector lever
“N” position

Brake pedal
depressed4WD shift switch:
2WD, AUTO or 4HBattery
voltage
4WD shift switch: 4H
to 4LO (While actua-
tor motor is operating.)Battery
voltage
→ 0V
4WD shift switch: 4LO
to 4H (While actuator
motor is operating.)0V →
Battery
voltage
4WD shift switch: 4LO 0V
SDIA2701E
Continuity should exist.
SDIA2702E