2004 INFINITI QX56 Ins

TF-68
TRANSFER FLUID TEMPERATURE SENSOR
Revision: August 20072004 QX56
4. CHECK INPUT SIGNAL
Without CONSULT-II
1. Turn ignition switch to ON position.
2. Check voltage between transfer control unit harness connector
E143 terminals 28 (B/G) and 31(G).
OK or NG
OK >> GO TO 5.
NG >> Check the following.

Continuity between transfer control unit and transfer
terminal cord assembly harness connector
5. PERFORM SELF-DIAGNOSIS AGAIN
After driving for a while, perform self-diagnosis again.
Refer to TF-27, "
Trouble Diagnosis without CONSULT-II" .
OK or NG
OK >> Inspection End.
NG >> 1. Perform transfer control unit input/output signal inspection. Refer to TF-55, "
TRANSFER CON-
TROL UNIT INSPECTION TABLE" .
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with harness
connector.Vo l ta g e
20°C (68°F) : Approx. 1.1V
80°C (176°F) : Approx. 0.3V
LDIA0072E

ATP SWITCH, WAIT DETECTION SWITCH AND NEUTRAL-4LO SWITCH
TF-71
C
E
F
G
H
I
J
K
L
MA
B
TF
Revision: August 20072004 QX56
6. CHECK SWITCH POWER SOURCE
Without CONSULT-II
1. Turn ignition switch to ON position.
2. Disconnect ATP switch F55, neutral-4LO switch F60, and wait detection switch F59 harness connectors.
3. Check voltage between the following terminals.
OK or NG
OK >> Inspection End.
NG >> GO TO 7.
7. PERFORM SELF-DIAGNOSIS AGAIN
After driving for a while, perform self-diagnosis again.
Refer to TF-27, "
Trouble Diagnosis without CONSULT-II" .
OK or NG
OK >> Inspection End.
NG >> 1. Perform transfer control unit input/output signal inspection. Refer to TF-55, "
TRANSFER CON-
TROL UNIT INSPECTION TABLE" .
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with harness
connector. ConnectorTe r m i n a l
(Wire color)Battery
voltage
E14340 (L)
Ground Yes 25 (V)
43 (G/Y)
WDIA0059E

CLUTCH PRESSURE SWITCH
TF-73
C
E
F
G
H
I
J
K
L
MA
B
TF
Revision: August 20072004 QX56
5. CHECK INPUT SIGNAL
With CONSULT-II
1. Turn ignition switch to ON position.
2. Select “ECU INPUT SIGNALS” in Data Monitor.
3. Put A/T selecor lever in D.
4. Turn 4WD shift switch to 4H and back to 2WD while reading out
ON/OFF status of "CL PRES SW".
OK or NG
OK >> GO TO 7.
NG >> Check the following.

Continuity between transfer control unit and transfer
terminal cord assembly harness connector

Clutch pressure switch.
Refer to TF-95, "
4WD SOLENOID VALVE, CLUTCH
PRESSURE SWITCH AND LINE PRESSURE
SWITCH" .
6. CHECK INPUT SIGNAL
Without CONSULT-II
1. Turn ignition switch to ON position and set 4WD shift switch to
4H position.
2. Check voltage between transfer control unit harness connector
E143 terminal 34 (BR) and ground. Refer to TF-55, "
Transfer
Control Unit Terminals and Reference Value"
OK or NG
OK >> GO TO 7.
NG >> Check the following.

Continuity between transfer control unit and transfer
terminal cord assembly harness connector

Clutch pressure switch.
Refer to TF-95, "
4WD SOLENOID VALVE, CLUTCH PRESSURE SWITCH AND LINE PRES-
SURE SWITCH" .
7. PERFORM SELF-DIAGNOSIS AGAIN
1. Check hydraulic parts.
2. After driving for a while, perform self-diagnosis again. Refer to TF-27, "
Trouble Diagnosis without CON-
SULT-II" .
OK or NG
OK >> Inspection End.
NG >> 1. Perform transfer control unit input/output signal inspection. Refer to TF-55, "
TRANSFER CON-
TROL UNIT INSPECTION TABLE" .
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with harness
connector.
SMT788D
WDIA0087E
LDIA0075E

LINE PRESSURE SWITCH
TF-75
C
E
F
G
H
I
J
K
L
MA
B
TF
Revision: August 20072004 QX56
5. CHECK INPUT SIGNAL
Without CONSULT-II
1. Turn ignition switch to ON position.
2. Check voltage between transfer control unit harness connector E143 terminal 35 (BR/W) and ground.
OK or NG
OK >> GO TO 6.
NG >> Check the following.

Continuity between transfer control unit and transfer terminal cord assembly harness connector

Line pressure switch
Refer to TF-95, "
4WD SOLENOID VALVE, CLUTCH PRESSURE SWITCH AND LINE PRES-
SURE SWITCH" .
6. PERFORM SELF-DIAGNOSIS AGAIN
1. Check hydraulic parts.
2. After driving for a while, perform self-diagnosis again. Refer to TF-27, "
Trouble Diagnosis without CON-
SULT-II" .
OK or NG
OK >> Inspection End.
NG >> 1. Perform transfer control unit input/output signal inspection. Refer to TF-55, "
TRANSFER CON-
TROL UNIT INSPECTION TABLE" .
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with harness
connector. After the vehicle has
been left for at least 5
minutes at room tem-
perature with ignition
switch OFF: Approx. 0 volts should
exist.
With ignition switch in
ON, 4WD shift switch in
AUTO or 4H and A/T
selector lever in D: Battery voltage should
exist.
LDIA0076E
LDIA0077E

TF-76
DATA ERASE/DISPLAY
Revision: August 20072004 QX56
DATA ERASE/DISPLAYPFP:00000
Diagnostic ProcedureEDS0018A
1. CHECK TRANSFER CONTROL UNIT POWER SOURCE
1. Turn ignition switch to OFF position and perform self-diagnosis
again.
Refer to TF-27, "
Trouble Diagnosis without CONSULT-II" and
TF-31, "
Trouble Diagnosis with CONSULT-II" .
2. Turn ignition switch to OFF position.
3. Disconnect transfer control unit harness connector E143.
4. Check voltage between transfer control unit harness connector
E143 terminal 47 (W) and ground.
OK or NG
OK >> GO TO 2.
NG >> Check the following.

No. 53 fuse (20A)

Harness continuity between fuse and transfer control unit
2. PERFORM SELF-DIAGNOSIS AGAIN
After driving for a while, perform self-diagnosis again.
Refer to TF-27, "
Trouble Diagnosis without CONSULT-II" and TF-31, "Trouble Diagnosis with CONSULT-II" .
OK or NG
OK >> Inspection End.
NG >> 1. Perform transfer control unit input/output signal inspection. Refer to TF-55, "
TRANSFER CON-
TROL UNIT INSPECTION TABLE" .
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with harness
connector. Voltage : Battery voltage
LDIA0078E

SHIFT ACTUATOR
TF-79
C
E
F
G
H
I
J
K
L
MA
B
TF
Revision: August 20072004 QX56
6. CHECK HARNESS CONTINUITY BETWEEN TRANSFER CONTROL UNIT AND TRANSFER CON-
TROL DEVICE
OK or NG
OK >> GO TO 7.
NG >> Repair and replace harness connector between transfer control unit and transfer control device.
7. PERFORM SELF-DIAGNOSIS AGAIN
After driving for a while, perform self-diagnosis again.
Refer to TF-27, "
Trouble Diagnosis without CONSULT-II" .
OK or NG
OK >> Inspection End.
NG >> 1. Perform transfer control unit/output signal inspection. Refer to TF-55, "
TRANSFER CONTROL
UNIT INSPECTION TABLE" .
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with harness
connector.

SHIFT ACTUATOR POSITION SWITCH
TF-81
C
E
F
G
H
I
J
K
L
MA
B
TF
Revision: August 20072004 QX56
5. CHECK INPUT SIGNAL
Without CONSULT-II
1. Start engine (idling).
2. Check voltage transfer control unit harness connector E143 ter-
minal 27 (W/L) [or 44 (LG/B)] and ground while 4WD shift switch
is set from 4H to 4LO (or from 4LO to 4H).
3. Result
OK or NG
OK >> GO TO 6.
NG >> Check the following.

Continuity between transfer control unit and transfer control device.

Check ground circuit between transfer control device and ground.
6. PERFORM SELF-DIAGNOSIS AGAIN
After driving for a while, perform self-diagnosis again.
Refer to TF-27, "
Trouble Diagnosis without CONSULT-II" .
OK or NG
OK >> Inspection End.
NG >> 1. Perform transfer control unit/output signal inspection. Refer to TF-55, "
TRANSFER CONTROL
UNIT INSPECTION TABLE" .
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with harness
connector.
SMT830D
Terminal ConditionVo l ta g e
(Approx.)
274WD shift switch is
set to 4HLess than 1V
4WD shift switch is
set except 4HBattery voltage
444WD shift switch is
set to 4LOLess than 1V
4WD shift switch is
set except 4LOBattery voltage

TF-84
SHIFT ACTUATOR CIRCUIT
Revision: August 20072004 QX56
6. CHECK INPUT SIGNAL
Without CONSULT-II
1. Start engine (idling).
2. Check voltage between transfer control unit harness connector
E142 terminal 4 (Y/L) [or 13 (G/B)] and ground while 4WD shift
switch is set from 4H to 4LO (or from 4LO to 4H).
3. Result
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7. CHECK HARNESS CONTINUITY BETWEEN TRANSFER CONTROL UNIT AND TRANSFER SHIFT
HIGH AND LOW RELAYS
OK or NG
OK >> GO TO 8.
NG >> Repair and replace harness connector between transfer control unit and transfer shift HIGH or
LOW relay.
8. PERFORM SELF-DIAGNOSIS AGAIN
After driving for a while, perform self-diagnosis again.
Refer to TF-27, "
Trouble Diagnosis without CONSULT-II" .
OK or NG
OK >> Inspection End.
NG >> 1. Perform transfer control unit/output signal inspection. Refer to TF-55, "
TRANSFER CONTROL
UNIT INSPECTION TABLE" .
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with harness
connector.
LDIA0083E
Terminal ConditionVo l ta g e
(Approx.)
4While actuator is
operating for 4H to
4LOBattery voltage
Actuator does not
operate0V
13While actuator is
operating for 4LO to
4HBattery voltage
Actuator does not
operate0V