2007 INFINITI QX56 air condition

TROUBLE DIAGNOSIS
TF-37
< SERVICE INFORMATION >
C
E
F
G
H
I
J
K
L
MA
B
TF
N
O
P
VHCL/S COMP [km/h] or
[mph]Vehicle speedVehicle stopped 0 km/h (0 MPH)
Vehicle running
CAUTION:
Check air pressure of tire under standard condition.Approximately
equal to the indica-
tion on speedome-
ter (Inside of
±10%)
COMP CL TORQ [kgm]Condition of control
torque• Vehicle stopped
• Engine running
• A/T selector lever “N” posi-
tion
• Brake pedal depressed4WD shift switch: 2WD 0 kg-m
4WD shift switch: AUTO39 - 1,353 N·m
(4 - 138 kg-m, 29 -
998 ft-lb)
4WD shift switch: 4H or
4LO1,353 N·m
(138 kg-m, 998 ft-
lb)
DUTY SOLENOID [%]Condition of clutch pres-
sure solenoid• Vehicle stopped
• Engine running
• A/T selector lever “N” posi-
tion
• Brake pedal depressed4WD shift switch: 2WD 4%
4WD shift switch: AUTO 96 - 4%
4WD shift switch: 4H or
4LO4%
2-4WD SOL [ON/OFF]Condition of 2-4WD shift
solenoid valve• Vehicle stopped
• Engine running
• A/T selector lever “N” posi-
tion
• Brake pedal depressed4WD shift switch: 2WD OFF
4WD shift switch: AUTO
ON 4WD shift switch: 4H
4WD shift switch: 4LO
4WD shift switch: AUTO
(“Wait” function is operat-
ing.)OFF
4WD shift switch: 4H
(“Wait” function is operat-
ing.)OFF
2-4WD SOL MON [ON/
OFF]Check signal for transfer
control unit signal output• Vehicle stopped
• Engine running
• A/T selector lever “N” posi-
tion
• Brake pedal depressed4WD shift switch: 2WD OFF
4WD shift switch: AUTO
ON 4WD shift switch: 4H
4WD shift switch: 4LO
4WD shift switch: AUTO
(“Wait” function is operat-
ing.)OFF
4WD shift switch: 4H
(“Wait” function is operat-
ing.)OFF
MOTOR RELAY [ON/
OFF]Condition of transfer mo-
tor relay• Accelerator pedal de-
pressed
• Vehicle stopped
• Engine running
• Brake pedal depressed4WD shift switch: 2WD OFF
4WD shift switch: AUTO
or 4LO (A/T selector lever
“P” or “N” position)OFF
("ON" for approx. 2
sec. after shifting
to “P” and “N”.)
4WD shift switch: AUTO
or 4LO (Except for A/T se-
lector lever “P” or “N” po-
sition)ON
4WD shift switch: 4H (A/T
selector lever “P” posi-
tion)OFF
("ON" for approx. 2
sec. after shifting
to “P”.)
4WD shift switch: 4H (Ex-
cept for A/T selector lever
“P” position)ON Monitored item [Unit] Content Condition Display value

TF-54
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS FOR SYSTEM
2.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-51, "
Power Supply Circuit for Transfer Control Unit"
.
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-48, "
Self-Diagnosis Procedure".
Vehicle Speed Sensor (ABS)INFOID:0000000003532532
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-26, "
CONSULT-II Func-
tion (ABS)".
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 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-26,
"CONSULT-II Function (ABS)".
Neutral-4LO SwitchINFOID:0000000003532533
CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE
Data are reference value.
TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE
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 mo-
tor is operating.)OFF → ON
4WD shift switch: 4LO to
4H (While actuator motor
is operating.)ON → OFF
4WD shift switch: 4LO ON

TF-56
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS FOR SYSTEM
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.
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-35, "
Transfer Control Unit Input/Output Signal Ref-
erence 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-115, "
Removal and Installation".
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)Continuity should exist.
SDIA2694E
Continuity should exist.
SDIA2695E
Terminal Condition Continuity
12 - 13Push neutral-4LO switch Yes
Release neutral-4LO switch No
SDIA2696E

TROUBLE DIAGNOSIS FOR SYSTEM
TF-59
< SERVICE INFORMATION >
C
E
F
G
H
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J
K
L
MA
B
TF
N
O
P
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-51, "
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-3
.
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.
Connector Terminal Voltage (Approx.)
M141 1 - Ground Battery voltage
PDIA0210E
Continuity should exist.SDIA2699E
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

TF-60
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS FOR SYSTEM
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-35, "
Transfer Control Unit Input/Output Signal Ref-
erence 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-115, "
Removal and Installation".
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 SwitchINFOID:0000000003532535
CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE
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

TF-62
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS FOR SYSTEM
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.
3.CHECK GROUND CIRCUIT
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect wait detection switch harness connector.
3. Check continuity between wait detection switch harness con-
nector F59 terminal 11 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 WAIT DETECTION SWITCH
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect wait detection switch harness connector.
3. Remove wait detection switch. Refer to TF-22, "
Location of Electrical Parts".
Connector Terminal ConditionVoltage
(Approx.)
E14343 -
Ground• Vehicle stopped
• Engine running
• A/T selector lever
“N” position
• Brake pedal de-
pressed4WD 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
SDIA2701E
Continuity should exist.
SDIA2702E
Continuity should exist.
SDIA2703E

TROUBLE DIAGNOSIS FOR SYSTEM
TF-63
< SERVICE INFORMATION >
C
E
F
G
H
I
J
K
L
MA
B
TF
N
O
P
4. Push and release wait detection switch and check continuity
between wait detection switch terminals 10 and 11.
OK or NG
OK >> GO TO 5.
NG >> Replace wait detection switch. Refer to TF-22, "
Loca-
tion of Electrical Parts".
5.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-35, "
Transfer Control Unit Input/Output Signal Ref-
erence 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-115, "
Removal and Installation".
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect wait detection switch harness connector.
3. Remove wait detection switch. Refer to TF-22, "
Location of Electrical Parts".
4. Push and release wait detection switch and check continuity
between wait detection switch terminals 10 and 11.
5. If NG, replace the wait detection switch. Refer to TF-22, "
Loca-
tion of Electrical Parts".
PNP Switch Signal (TCM)INFOID:0000000003532536
DIAGNOSTIC PROCEDURE
1.CHECK DTC WITH TCM
Perform self-diagnosis with TCM. Refer to AT-83, "
CONSULT-II Function (A/T)".
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 Value".
OK or NG
OK >> GO TO 3.
Terminal Condition Continuity
10 - 11Push wait detection switch Yes
Release wait detection switch No
SDIA2704E
Terminal Condition Continuity
10 - 11Push wait detection switch Yes
Release wait detection switch No
SDIA2704E

TF-64
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS FOR SYSTEM
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 AT-83, "
CONSULT-II Function (A/T)".
Actuator MotorINFOID:0000000003532537
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.
Monitored item Content Condition Display value
SHIFT ACT1 [ON/OFF]Output condition to ac-
tuator motor (High)• Vehicle stopped
• Engine running
• A/T selector lever “N”
position
• Brake pedal depressed4WD shift switch: 4H to
4LO (“Wait” function is op-
erating.)ON
Except the above OFF
SHIFT AC MON1 [ON/OFF]Check signal for trans-
fer control unit signal
output• Vehicle stopped
• Engine running
• A/T selector lever “N”
position
• Brake pedal depressed4WD shift switch: 4H to
4LO (“Wait” function is op-
erating.)ON
Except the above OFF
SHIFT ACT2 [ON/OFF]Output condition to ac-
tuator motor (Low)• Vehicle stopped
• Engine running
• A/T selector lever “N”
position
• Brake pedal depressed4WD shift switch: 4LO to
4H (“Wait” function is op-
erating.)ON
Except the above OFF
SHIFT AC MON2 [ON/OFF]Check signal for trans-
fer control unit signal
output• Vehicle stopped
• Engine running
• A/T selector lever “N”
position
• Brake pedal depressed4WD shift switch: 4LO to
4H (“Wait” function is op-
erating.)ON
Except the above OFF
Te r m i n a lWire
colorItem Condition Data (Approx.)
4 Y/L Transfer shift high relay• Vehicle stopped
• Engine running
• A/T selector le-
ver “N” position
• Brake pedal de-
pressed4WD shift switch: 4H to 4LO (“Wait” func-
tion is operating.)Battery voltage
Except the above 0V
13 G/B Transfer shift low relay• Vehicle stopped
• Engine running
• A/T selector le-
ver “N” position
• Brake pedal de-
pressed4WD shift switch: 4LO to 4H (“Wait” func-
tion is operating.)Battery voltage
Except the above 0V
33 R/LTransfer shift high relay moni-
tor• Vehicle stopped
• Engine running
• A/T selector le-
ver “N” position
• Brake pedal de-
pressed4WD shift switch: 4H to 4LO (“Wait” func-
tion is operating.)Battery voltage
Except the above 0V