INFINITI QX56 2006 Factory Service Manual
Manufacturer: INFINITI, Model Year: 2006, Model line: QX56, Model: INFINITI QX56 2006Pages: 3383, PDF Size: 51.76 MB
Page 3161 of 3383
TF-56
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: November 20092006 QX56
2. CHECK GROUND CIRCUIT
1. Turn ignition switch “ OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector.
3. Check continuity between transfer control unit harness connec- tor E142 terminals 3, 6, E143 terminal 45 and ground.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
3. 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 4.
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.
4. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "
Removal and Installation" .
Continuity should exist.
SDIA2691E
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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
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TF-58
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: November 20092006 QX56
Output Shaft Revolution Signal (TCM)EDS002I6
DIAGNOSTIC PROCEDURE
1. CHECK DTC WITH TCM
Perform self-diagnosis with TCM. Refer to TF-50, "
SELF-DIAGNOSTIC PROCEDURE (WITH CONSULT-II)" .
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-54, "
TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
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 TCM again. Refer to TF-50, "
SELF-DIAGNOSTIC PROCEDURE
(WITH CONSULT-II)" .
Vehicle Speed Sensor (ABS)EDS002I7
DIAGNOSTIC PROCEDURE
1. CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Perform self-diagnosis with ABS actuator and electric unit (control unit). Refer to BRC-29, "
SELF-DIAGNO-
SIS" .
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-54, "
TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
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 ABS actuator and electric unit (control unit) again. Refer to BRC-29,
"SELF-DIAGNOSIS" .
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TROUBLE DIAGNOSIS FOR SYSTEMTF-59
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Revision: November 2009 2006 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 ConditionDisplay value
N POSI SW TF [ON/
OFF] Condition of neutral-4LO
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
TerminalWire
color Item
ConditionData (Approx.)
25 V Neutral-4LO 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
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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
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TROUBLE DIAGNOSIS FOR SYSTEMTF-61
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Revision: November 2009 2006 QX56
3. CHECK GROUND CIRCUIT
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect neutral-4LO switch harness connector.
3. Check continuity between neutral-4LO switch harness connec- tor F60 terminal 12 and ground.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK 4LO SWITCH
1. Turn ignition switch “OFF”.
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.
OK or NG
OK >> GO TO 5.
NG >> Replace neutral-4LO switch. Refer to TF-22, "
Location
of Electrical Parts" .
5. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-54, "
TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG
OK >> GO TO 6.
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.
6. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "
Removal and Installation" .
Continuity should exist.
SDIA2695E
Terminal
Condition Continuity
12 - 13 Push neutral-4LO switch
Yes
Release neutral-4LO switch No
SDIA2696E
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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
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TROUBLE DIAGNOSIS FOR SYSTEMTF-63
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Revision: November 2009 2006 QX56
DIAGNOSTIC PROCEDURE
1. CHECK 4WD SHIFT SWITCH SIGNAL
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR ” mode for “ALL MODE AWD/4WD ” with CONSULT-II.
3. Read out ON/OFF switching action of the “2WD SWITCH”,
“AUTO SWITCH”, “LOCK SWITCH”, “4L SWITCH ” with operat-
ing 4WD shift switch.
Without CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Check voltage between transfer control unit harness connector terminals and ground.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
SDIA2697E
Connector Terminal ConditionVoltage
(Approx.)
E142 9 - ground
4WD shift switch: 2WD
Battery voltage
4WD shift switch: AUTO, 4H or 4LO 0V
18 - ground 4WD shift switch: 4H
Battery voltage
4WD shift switch: 2WD, AUTO or
4LO 0V
23 - ground 4WD shift switch: 4LO
Battery voltage
4WD shift switch: 2WD, AUTO or
4H 0V
24 - ground 4WD shift switch: AUTO
Battery voltage
4WD shift switch: 2WD, 4H or 4LO 0V
WDIA0148E
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TF-64
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: November 20092006 QX56
2. CHECK 4WD SHIFT SWITCH POWER SUPPLY CIRCUIT
1. Turn ignition switch “ OFF”. (Stay for at least 5 seconds.)
2. Disconnect 4WD shift switch harness connector.
3. Check voltage between 4WD shift switch harness connector ter- minal 1 and ground.
4. Turn ignition switch “ ON”. (Do not start engine.)
5. Check voltage between 4WD shift switch harness connector ter- minal 1 and ground.
OK or NG
OK >> GO TO 3.
NG >> Go to TF-54, "
Power Supply Circuit For Transfer Control
Unit" .
3. CHECK HARNESS BETWEEN 4WD SHIFT SWITCH AND TRANSFER CONTROL UNIT
1. Turn ignition switch “ OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the 4WD shift switch harness connector.
3. Check continuity between the following terminals.
–Transfer control unit harness connector E142 terminal 9 and
4WD shift switch harness connector M141 terminal 2.
–Transfer control unit harness connector E142 terminal 18 and
4WD shift switch harness connector M141 terminal 5.
–Transfer control unit harness connector E142 terminal 23 and
4WD shift switch harness connector M141 terminal 6.
–Transfer control unit harness connector E142 terminal 24 and
4WD shift switch harness connector M141 terminal 3.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Check the following. If any items are damaged, repair or replace damaged parts.
Harness for short or open between battery and transfer shut off relay harness connector E69
terminal 3.
Power supply circuit for transfer control unit. Refer to PG-4, "POWER SUPPLY ROUTING CIR-
CUIT" .
Connector Terminal Voltage (Approx.)
M141 1 - Ground 0V
SDIA2383E
ConnectorTerminal Voltage (Approx.)
M141 1 - Ground Battery voltage
PDIA0210E
Continuity should exist.SDIA2699E
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TROUBLE DIAGNOSIS FOR SYSTEMTF-65
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Revision: November 2009 2006 QX56
4. CHECK 4WD SHIFT SWITCH
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect 4WD shift switch harness connector.
3. Operate 4WD shift switch and check continuity between 4WD shift switch terminals.
OK or NG
OK >> GO TO 5.
NG >> Replace 4WD shift switch.
5. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-54, "
TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG
OK >> GO TO 6.
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.
6. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-132, "
Removal and Installation" .
Connector TerminalConditionContinuity
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