ECO mode INFINITI QX56 2006 Factory Service Manual

TROUBLE DIAGNOSISTF-35
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Revision: November 2009 2006 QX56
NOTE:

Light tight-corner braking symptom may occur depending on driving conditions in AUTO mode. This is not
a malfunction.

Heavy tight-corner braking symptom occurs when vehicle is driven in the following conditions: 4WD shift
switch is "4H" or "4LO", steering wheel is turned fully to either side.
Transfer Control Unit Input/Output Signal Reference ValuesEDS002HJ
TRANSFER CONTROL UNIT INSPECTION TABLE
Specifications with CONSULT-II
4WD warning lamp flashes slowly
(1 time/2 seconds)While drivingTire size is different between front and
rear of vehicle.
TF-129
Transfer fluid temperature
Clutch pressure switch
Heavy tight-corner braking symptom occurs
(See NOTE.)

While driving

AUTO mode

Steering wheel is
turned fully to either
side CAN communication line
TF-130
4WD shift switch
Accelerator pedal position signal
Clutch pressure solenoid
Transfer inner parts
4WD system does not operate While driving 4WD shift switch
TF-131
Clutch pressure switch
Transfer inner parts
Symptom
ConditionCheck itemReference page
Monitored item [Unit] Content ConditionDisplay value
VHCL/S SEN ·FR [km/h]
or [mph] Front wheel speed Vehicle stopped
0 km/h (0 MPH)
Vehicle running
CAUTION:
Check air pressure of tire under standard condition. Approximately
equal to the indi-
cation on speed-
ometer (Inside of
±
10%)
VHCL/S SEN ·RR [km/h]
or [mph] Rear wheel speed Vehicle stopped
0 km/h (0 MPH)
Vehicle running
CAUTION:
Check air pressure of tire under standard condition. Approximately
equal to the indi-
cation on speed-
ometer (Inside of
±
10%)
ENGINE SPEED [rpm] Engine speed Engine stopped
(Engine speed: Less than 400 rpm)
0 rpm
Engine running
(Engine speed: 400 rpm or more) Approximately
equal to the indi-
cation on tachom-
eter
THRTL POS SEN [V] Accelerator pedal posi-
tion (APP) sensor signal
voltage Accelerator pedal: Release
Approx. 0.5V
Accelerator pedal: Fully depressed Approx. 4.0V
FLUID TEMP SE [V] Transfer fluid tempera-
ture signal voltage Transfer fluid temperature approx. 20 - 80°C (68 - 176
°F) Approx. 1.1 - 0.3V
BATTERY VOLT [V] Power supply voltage for
transfer control unit
Ignition switch: ON
Battery voltage
2WD SWITCH [ON/OFF] Input condition from
4WD shift switch 4WD shift switch: 2WD
ON
4WD shift switch: AUTO, 4H or 4LO OFF
AUTO SWITCH [ON/
OFF] Input condition from
4WD shift switch 4WD shift switch: AUTO
ON
4WD shift switch: 2WD, 4H or 4LO OFF

TF-48
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
P POSI SW AT [ON/OFF]ז ד
P ” position signal of A/T PNP 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
control 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
output.
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 dis-
played.
4L IND [ON/OFF] ––×Control status of 4LO indicator lamp is dis-
played.
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 (clock-
wise)
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
Monitored item (Unit)
Monitor item selection
Remarks
ECU INPUT
SIGNALS MAIN
SIGNALS SELEC-
TION FROM MENU

TF-54
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: November 20092006 QX56
TROUBLE DIAGNOSIS FOR SYSTEMPFP:00000
Power Supply Circuit For Transfer Control UnitEDS002I4
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 ConditionDisplay value
BATTERY VOLT [V] Power supply voltage for
transfer control unit Ignition switch: ON
Battery voltage
Te r m i n a lWire
color Item
ConditionData (Approx.)
3 B Ground Always0V
6 B Ground Always0V
16 Y/R Power supply Ignition switch: ON
Battery voltage
Ignition switch: OFF
(5 seconds after Ignition switch is turned OFF) 0V
22 Y/R Power supply Ignition switch: ON
Battery voltage
Ignition switch: OFF
(5 seconds after Ignition switch is turned OFF) 0V
29 L/W Ignition switch monitor Ignition switch: ON
Battery voltage
Ignition switch: OFF 0V
30 SB Shut off relay Ignition switch: ON
0V
Ignition switch: OFF
(5 seconds after Ignition switch is turned OFF) Battery voltage
45 B Ground Always0V
47 W Power supply
(Memory back-up) Ignition switch: ON
Battery voltage
Ignition switch: OFF Battery voltage

TROUBLE DIAGNOSIS FOR SYSTEMTF-57
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Revision: November 2009 2006 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

TF-60
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: November 20092006 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 and neutral-4LO switch harness connector
F60 terminal 13.
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 depressed 4WD shift switch: 2WD,
AUTO or 4H
OFF
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
ConnectorTerminal
(Wire
color) Condition
Voltage
(Approx.)
E143 25 -
Ground

Vehicle stopped

Engine running

A/T selector lever
“ N ” position

Brake pedal
depressed 4WD shift switch:
2WD, AUTO or 4H
Battery
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: November 20092006 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 SwitchEDS002I9
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 - 13 Push neutral-4LO switch
Yes
Release neutral-4LO switch No
SDIA2696E
Monitored item [Unit]Content ConditionDisplay value
2WD SWITCH [ON/
OFF] Input condition from 4WD
shift switch 4WD shift switch: 2WD
ON
4WD shift switch: AUTO, 4H or 4LO OFF
AUTO SWITCH [ON/
OFF] Input condition from 4WD
shift switch 4WD shift switch: AUTO
ON
4WD shift switch: 2WD, 4H or 4LO OFF
LOCK SWITCH [ON/
OFF] Input condition from 4WD
shift switch 4WD shift switch: 4H
ON
4WD shift switch: 2WD, AUTO or 4LO OFF
4L SWITCH [ON/OFF] Input condition from 4WD
shift switch 4WD 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 depressed 4WD 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
color Item
ConditionData (Approx.)
9G/W 4WD shift switch
(2WD) Ignition switch: ON4WD shift switch: 2WD
Battery voltage
4WD shift switch: AUTO, 4H or 4LO 0V
18 O 4WD shift switch
(4H) Ignition switch: ON4WD shift switch: 4H
Battery voltage
4WD shift switch: 2WD, AUTO or 4LO 0V
23 R 4WD shift switch
(4LO) Ignition switch: ON4WD shift switch: 4LO
Battery voltage
4WD shift switch: 2WD, AUTO or 4H 0V
24 LG/R 4WD 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: November 20092006 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
ConditionContinuity
M141 1 - 2
4WD shift switch: 2WD
Yes
4WD shift switch: AUTO, 4H and
4LO No
1 - 3 4WD shift switch: AUTO
Yes
4WD shift switch: 2WD, 4H and
4LO No
1 - 4 4WD shift switch: 2WD
No
4WD shift switch: AUTO, 4H and
4LO Ye s
1 - 5 4WD shift switch: 4H
Yes
4WD shift switch: 2WD, AUTO,
and 4LO No
1 - 6 4WD shift switch: 4LO
Yes
4WD shift switch: 2WD, AUTO
and 4H No
WDIA0205E
Monitored item
Content ConditionDisplay value
WAIT DETCT SW [ON/
OFF] Condition of wait detection
switch

Vehicle stopped

Engine running

A/T selector lever
“N ”
position

Brake pedal depressed 4WD shift switch: 2WD,
AUTO or 4H
OFF
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
color Item
ConditionData (Approx.)
43 G/Y Wait detection switch

Vehicle stopped

Engine running

A/T selector
lever “N ” position

Brake pedal
depressed 4WD 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 SYSTEMTF-67
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Revision: November 2009 2006 QX56
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 and wait detection switch harness connec-
tor F59 terminal 10.
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 depressed 4WD shift switch: 2WD, AUTO
or 4H
OFF
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
Connector Terminal ConditionVoltage
(Approx.)
E143 43 -
Ground

Vehicle stopped

Engine running

A/T selector lever
“ N ” position

Brake pedal
depressed 4WD shift switch:
2WD, AUTO or 4H
Battery
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 0VSDIA2701E
Continuity should exist.
SDIA2702E

TROUBLE DIAGNOSIS FOR SYSTEMTF-85
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Revision: November 2009 2006 QX56
7. 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
“SHIFT ACT CIR [P1819]” displayed?
YES >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
NO >> Inspection End.
8. 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 transfer control device?
YES >> Replace transfer control unit. Refer to TF-132, "Removal and Installation" .
NO >> Inspection End.
Engine Speed Signal (ECM)EDS002IF
DIAGNOSTIC PROCEDURE
1. CHECK DTC WITH ECM
Perform self-diagnosis with ECM. Refer to EC-118, "
SELF-DIAG RESULTS MODE" .
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2.
2. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-35, "
Transfer Control Unit Input/Output Signal Ref-
erence Values" .
OK or NG
OK >> GO TO 3.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
3. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Perform self-diagnosis with ECM again. Refer to EC-118, "
SELF-DIAG RESULTS MODE" .

TF-102
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: November 20092006 QX56
COMPONENT INSPECTION
Transfer Motor Relay
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer motor relay. Refer to TF-22, "
Location of Electrical Parts" .
3. Apply 12V direct current between transfer motor relay terminals 1 and 2.
4. Check continuity between relay terminals 3 and 5.
5. If NG, replace transfer motor relay. Refer to TF-22, "
Location of
Electrical Parts" .
Transfer Motor
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer motor. Refer to TF-142, "
Removal and Installation" .
3. Apply 12V direct current between transfer motor terminals 14 and 15.
4. If transfer motor does not operate, replace transfer motor. Refer to TF-142, "
Removal and Installation" .
Transfer Fluid TemperatureEDS002IJ
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. Condition
Continuity
12V direct current supply between terminals 1 and 2 Yes
OFF No
LDIA0098E
LDIA0097E
Monitored item [Unit]Content ConditionDisplay value
(Approx.)
FLUID TEMP SE [V] Condition of transfer fluid
temperature Transfer fluid temperature approx. 20 - 80
°C (68 -
176° F) 1.1 - 0.3V
Te r m i n a lWire
color Item
ConditionData (Approx.)
28 B/G Sensor ground Always0V
31 G Transfer fluid temperature
sensor
Ignition switch: ONTransfer fluid temperature approx. 20°C
(68
°F) 1.1V
Transfer fluid temperature approx. 80°C
(176 °F) 0.3V