INFINITI QX56 2004 Factory Service Manual

TF-66
TRANSFER FLUID TEMPERATURE SENSOR
Revision: August 20072004 QX56
TRANSFER FLUID TEMPERATURE SENSORPFP:00000
Diagnostic ProcedureEDS00186
1. CHECK TRANSFER FLUID TEMPERATURE SENSOR
Refer to TF-95, "
2-4WD SHIFT SOLENOID VALVE AND TRANSFER FLUID TEMPERATURE SENSOR" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace fluid temperature sensor.
2. CHECK INPUT SIGNAL
Do you have CONSULT-II?
Ye s o r N o
Yes >> GO TO 3.
No >> GO TO 4.

TRANSFER FLUID TEMPERATURE SENSOR
TF-67
C
E
F
G
H
I
J
K
L
MA
B
TF
Revision: August 20072004 QX56
3. CHECK INPUT SIGNAL
With CONSULT-II
1. Start engine.
2. Select “ECU INPUT SIGNALS” in Data Monitor.
3. Read out the value of “FLUID TEMP SE”.
OK or NG
OK >> GO TO 5.
NG >> Check the following.

Continuity between transfer control unit and transfer terminal cord assembly harness connectorVo l ta g e
20°C (68°F) : Approx. 1.1V
80°C (176°F) : Approx. 0.3V
SMT784D
SMT974D

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-69
C
E
F
G
H
I
J
K
L
MA
B
TF
Revision: August 20072004 QX56
ATP SWITCH, WAIT DETECTION SWITCH AND NEUTRAL-4LO SWITCHPFP:00000
Diagnostic ProcedureEDS00187
1. CHECK ATP SWITCH, WAIT DETECTION SWITCH AND NEUTRAL-4LO SWITCH
Refer to TF-96, "
ATP SWITCH, NEUTRAL-4LO SWITCH AND WAIT
DETECTION SWITCH" .
OK or NG
OK >> GO TO 2.
NG >> Replace ATP switch, neutral-4LO switch, or wait detec-
tion switch.
2. CHECK INPUT SIGNAL
Do you have CONSULT-II?
Ye s o r N o
Yes >> GO TO 3.
No >> GO TO 4.
3. CHECK INPUT SIGNAL
With CONSULT-II
1. Select “SELECTIONS FROM MENU” in Data Monitor.
2. Select “ATP SWITCH”, “N POSI SW TF” or “WAIT DETCT SW”.
3. Read out the ON/OFF status of “ATP SWITCH”, “N POSI SW
TF” or “WAIT DETCT SW”. Refer to TF-38, "
REFERENCE
VALUE IN DATA MONITOR MODE" .
OK or NG
OK >> GO TO 7.
NG >> Check the following.

Harness continuity between neutral-4LO switch, ATP
switch, wait detection switch harness connectors and
transfer control unit

Continuity between neutral-4LO switch, ATP switch, wait detection switch harness connectors
and ground
SMT786D
WDIA0086E

TF-70
ATP SWITCH, WAIT DETECTION SWITCH AND NEUTRAL-4LO SWITCH
Revision: August 20072004 QX56
4. CHECK HARNESS GROUND CONTINUITY
Without CONSULT-II
1. Turn ignition switch to OFF position.
2. Disconnect ATP switch F55, neutral-4LO switch F60, and wait detection switch F59 harness connectors.
3. Check continuity from harness connectors to ground.
OK or NG
OK >> GO TO 5.
NG >> Check the following.

Circuit between neutral-4LO switch, ATP switch, wait
detection switch harness connectors and ground
5. CHECK HARNESS CONTINUITY
Without CONSULT-II
1. Turn ignition switch to OFF position.
2. Disconnect transfer control unit E143, ATP switch F55, neutral-4LO switch F60, and wait detection switch
F59 harness connectors.
3. Check continuity between the following terminals.
OK or NG
OK >> GO TO 6.
NG >> Check the following.

Circuits between transfer control unit harness con-
nector and neutral-4LO switch, ATP switch, and wait detection switch harness connectors. ConnectorTe r m i na l
(Wire color)Continuity
F55 9 (B)
Ground Yes F60 12 (B)
F59 11 (B)
WDIA0076E
Connec-
torTe r m i n a l
(Wire
color)Connec-
torTe r m i n a l
(Wire
color)Continu-
ity
F55 8 (L/Y)
E14340 (L)
Ye s F60 13 (V) 25 (V)
F59 10 (G/Y) 43 (G/Y)
WDIA0077E

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

TF-72
CLUTCH PRESSURE SWITCH
Revision: August 20072004 QX56
CLUTCH PRESSURE SWITCHPFP:00000
Diagnostic ProcedureEDS00188
1. CHECK MALFUNCTION
Is this malfunction detected only while driving in reverse?
Ye s o r N o
Yes >> Check A/T PNP switch "R" position.

Refer to AT-109, "DTC P0705 PARK/NEUTRAL POSITION SWITCH" .
No >> GO TO 2.
2. CHECK OTHER MALFUNCTION
Are other malfunctions also detected by self-diagnosis and CONSULT-II?
Refer to TF-27, "
Trouble Diagnosis without CONSULT-II" and TF-31, "Trouble Diagnosis with CONSULT-II" .
Ye s o r N o
Yes >> Check for other malfunctions.

(When other malfunctions are eliminated, clutch pressure switch malfunction display may dis-
appear.)
No >> GO TO 3.
3. CHECK 2-4WD SHIFT SOLENOID VALVE AND 4WD SHIFT SWITCH CIRCUITS
Check 2-4WD shift solenoid valve and 4WD shift switch circuits.
OK or NG
OK >> GO TO 4.
NG >> Check, repair or replace faulty parts.
4. CHECK INPUT SIGNAL
Do you have CONSULT-II?
Ye s o r N o ?
Yes >> GO TO 5.
No >> GO TO 6.

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

TF-74
LINE PRESSURE SWITCH
Revision: August 20072004 QX56
LINE PRESSURE SWITCHPFP:00000
Diagnostic ProcedureEDS00189
1. CHECK MALFUNCTION
Is this malfunction detected only while driving in reverse?
Ye s o r N o
Yes >> Check A/T PNP switch “R” position.

Refer to AT-109, "DTC P0705 PARK/NEUTRAL POSITION SWITCH" .
No >> GO TO 2.
2. CHECK OTHER MALFUNCTIONS
Are other malfunctions also detected by self-diagnosis and CONSULT-II?
Refer to TF-27, "
Trouble Diagnosis without CONSULT-II" and TF-31, "Trouble Diagnosis with CONSULT-II" .
Ye s o r N o
Yes >> Check for other malfunctions.

(When other malfunctions are eliminated, line pressure switch malfunction display may disap-
pear.)
No >> GO TO 3.
3. CHECK INPUT SIGNAL
Do you have CONSULT-II?
Ye s o r N O
Yes >> GO TO 4.
No >> GO TO 5.
4. CHECK INPUT SIGNAL
With CONSULT-II
1. Select “ECU INPUT SIGNALS” in Data Monitor.
2. Put A/T selector lever in D.
3. Turn the 4WD shift switch to 4H and back to 2WD while reading
out ON/OFF status of "LINE PRES SW".
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 PRESSURE
SWITCH" .
SMT790D
WDIA0087E

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