clutch INFINITI QX4 2001 Factory Service Manual

SMT968D
1. Current CLUTCH FORCE RELEASE LIMIT value ª0.3 kg-mº
appears under ªCONDITION SETTINGº on CONSULT-II dis-
play.
2. Touch ª1.2º on the display.
SMT969D
3. Display changes to ªNOW ADJUSTINGº in a short time.
SMT970D
4. When clutch force release limit value is set to ª1.2 kg-mº, cur-
rent value ª0.3 kg-mº shown on display will be replaced by ª1.2
kg-mº and ªADJUSTING COMPLETEº will appear at the same
time. Clutch force release limit value setting is now complete.
ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION
Trouble Diagnosis with CONSULT-II (Cont'd)
TF-40

Terminal
No.Item Condition Judgement standard
31Transfer fluid tempera-
ture sensor
&
At 20ÉC (68ÉF) Approx. 1.5V
At 80ÉC (176ÉF) Approx. 0.5V
32 ABS signalWhen moving, use the CONSULT-II
pulse frequency measuirng func-
tion.*2
CAUTION:
Connect the diagnosis data link
cable to the vehicle diagnosis con-
nector.
*2: A circuit tester cannot be used to
test this item.Refer to the illustration
(SMT973D) at the end of
this section.
33Transfer shift relay
(High)While actuator is operating from ª4Hº
to ª4LOºBattery voltage
Actuator does not operate. Approx. 0V
34 Clutch pressure switch4WD shift switch is set to ªAUTOº or
ª4Hº, then A/T selector lever is set to
ªDº position. (wait detection system:
OFF)Battery voltage
4WD shift switch is set to ª2WDº,
ªAUTOº or ª4Hº, then A/T selector
lever is set to ªDº position. (wait
detection system: ON)Approx. 0V
35 Line pressure switch4WD shift switch is set to ª2WDº,
ªAUTOº or ª4Hº, then A/T selector
lever is set to ªDº position.Battery voltage
Ð Approx. 0V
36 CONSULT-II (RX) Ð Ð Ð
37 Tachometer
ÐRefer to EC-127, ªECM
Inspection Tableº.
38 Front revolution sensor
4WD shift switch is set to ª4Hº posi-
tion. A/T selector lever is set to ªDº
position.Approx. 1V [30 km/h (19
MPH)]
Voltage rises in
response to vehicle
speed.
TROUBLE DIAGNOSIS Ð GENERAL DESCRIPTION
Transfer Control Unit Terminals and Reference Value (Cont'd)
TF-58

Diagnostic ProcedureNBTF0020
1 CHECK 4WD SOLENOID VALVE
SMT775D
Refer to ª4WD Solenoid Valve, Clutch Pressure Switch and Line Pressure Switchº, ªCOMPONENT INSPECTIONº, TF-111.
OK or NG
OK©GO TO 2.
NG©Check the following. If OK, repair or replace 4WD solenoid valve.
IContinuity of transfer sub-harness
Refer to ªTRANSFER TERMINAL CORD ASSEMBLY SUB-HARNESS CONNECTORº,
ªCOMPONENT INSPECTIONº, TF-114.
2 CHECK POWER SOURCE CIRCUIT
1. Turn ignition switch to ªOFFº position.
2. Disconnect transfer control unit harness connector.
3. Check resistance between transfer terminal cord assembly sub-harness connector terminal 6 and transfer control unit
harness connector terminal 10.
Resistance: 11.2 - 12.8W
SMT776D
OK or NG
OK©GO TO 3.
NG©Check the following.
ITransfer dropping resistor
Refer to ªTransfer Dropping Resistorº, ªCOMPONENT INSPECTIONº, TF-112.
IContinuity between transfer terminal cord assembly sub-harness connector terminal 6
and transfer control unit harness connector terminal 10.
4WD SOLENOID VALVE
Diagnostic Procedure
TF-64

Diagnostic ProcedureNBTF0025
1 CHECK MALFUNCTION
Is this malfunction detected only while driving in reverse?
YesorNo
Ye s©CHECK A/T PNP SWITCH ªRº POSITION.
Refer to AT-99, ªDTC P0705 Park/Neutral Position Switchº.
No©GO TO 2.
2 CHECK OTHER MALFUNCTION
Are other malfunctions also detected by self-diagnosis and CONSULT-II?
Refer to ªTrouble Diagnosis without CONSULT-IIº, TF-27 and ªTrouble Diagnosis with CONSULT-IIº, TF-30.
YesorNo
Ye s©CHECK FOR OTHER MALFUNCTIONS.
(When other malfunctions are eliminated, clutch pressure switch malfunction display may
disappear.)
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
WITH CONSULT-II©GO TO 5.
WITHOUT CONSULT-II©GO TO 6.
CLUTCH PRESSURE SWITCH
Diagnostic Procedure
TF-80

5 CHECK INPUT SIGNAL
With CONSULT-II
1. Turn ignition switch to ªONº position.
2. Select ªECU INPUT SIGNALSº in Data Monitor.
3. Read out ON/OFF status of ªCL PRES SWº.
SMT788D
SMT977D
OK or NG
OK©GO TO 7.
NG©Check the following.
IContinuity between transfer control unit and transfer terminal cord assembly sub-har-
ness connector
ITransfer sub-harness
IClutch pressure switch
Refer to ª4WD Solenoid Valve, Clutch Pressure Switch and Line Pressure Switchº,
ªCOMPONENT INSPECTIONº, TF-111.
GI
MA
EM
LC
EC
FE
AT
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
CLUTCH PRESSURE SWITCH
Diagnostic Procedure (Cont'd)
TF-81

6 CHECK INPUT SIGNAL
Without CONSULT-II
1. Turn ignition switch to ªONº position and set 4WD shift switch to ª4Hº position.
2. Check voltage between transfer control unit harness connector terminal 34 and body ground.
When 4WD shift switch is in ª2WDº:
Battery voltage should exist.
When 4WD shift switch is in ªAUTOº or ª4Hº and A/T selector lever is in ªDº:
ªWaitº operating: Battery voltage should exist.
ªWaitº not operating: Approx. 0 volts should exist.
SMT789D
SMT849D
OK or NG
OK©GO TO 7.
NG©Check the following.
IContinuity between transfer control unit and transfer terminal cord assembly sub-har-
ness connector
ITransfer sub-harness
IClutch pressure switch
Refer to ª4WD Solenoid Valve, Clutch Pressure Switch and Line Pressure Switchº,
ªCOMPONENT INSPECTIONº, TF-111.
7 PERFORM SELF-DIAGNOSIS AGAIN
1. Check hydraulic parts.
2. After driving for a while, perform self-diagnosis again. Refer to ªTrouble Diagnosis without CONSULT-IIº, TF-27.
OK or NG
OK©INSPECTION END
NG©1. Perform transfer control unit input/output signal inspection. Refer to ªTRANSFER
CONTROL UNIT INSPECTION TABLEº, TF-55.
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with
harness connector.
CLUTCH PRESSURE SWITCH
Diagnostic Procedure (Cont'd)
TF-82

4 CHECK INPUT SIGNAL
SMT790D
With CONSULT-II
1. Select ªECU INPUT SIGNALSº in Data Monitor.
2. Read out the ON/OFF status of ªLINE PRES SWº.
SMT977D
OK or NG
OK©GO TO 6.
NG©Check the following.
IContinuity between transfer control unit and transfer terminal cord assembly sub-har-
ness connector
ITransfer sub-harness
ILine pressure switch
Refer to ª4WD Solenoid Valve, Clutch Pressure Switch and Line Pressure Switchº,
ªCOMPONENT INSPECTIONº, TF-111.
LINE PRESSURE SWITCH
Diagnostic Procedure (Cont'd)
TF-84

5 CHECK INPUT SIGNAL
Without CONSULT-II
1. Turn ignition switch to ªOFFº position.
2. Disconnect transfer control unit harness connector.
3. Check continuity between transfer control unit harness connector terminal 35 and body ground.
After the vehicle has been left for at least 5 minutes in a room temperature with ignition switch ªOFFº:
No continuity should exist.
With ignition switch in ªONº, 4WD shift switch in ªAUTOº or ª4Hº and A/T selector lever in ªDº:
Continuity should exist.
SMT791D
SMT849D
OK or NG
OK©GO TO 6.
NG©Check the following.
IContinuity between transfer control unit and transfer terminal cord assembly sub-har-
ness connector
ITransfer sub-harness
ILine pressure switch
Refer to ª4WD Solenoid Valve, Clutch Pressure Switch and Line Pressure Switchº,
ªCOMPONENT INSPECTIONº, TF-111.
6 PERFORM SELF-DIAGNOSIS AGAIN
1. Check hydraulic parts.
2. After driving for a while, perform self-diagnosis again. Refer to ªTrouble Diagnosis without CONSULT-IIº, TF-27.
OK or NG
OK©INSPECTION END
NG©1. Perform transfer control unit input/output signal inspection. Refer to TF-55.
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with
harness connector.
GI
MA
EM
LC
EC
FE
AT
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
LINE PRESSURE SWITCH
Diagnostic Procedure (Cont'd)
TF-85

Symptom 8. Tight Corner Braking SymptomNBTF0036SYMPTOM: Tight corner braking symptom occurs. (Hydraulic
system failure)
1 CHECK INPUT SIGNAL
With CONSULT-II
1. Select ªECU INPUT SIGNALSº in Data Monitor.
2. Read out the ON/OFF status of ªCLUTCH PRES SWº.
SMT977D
Without CONSULT-II
Check voltage between transfer control unit harness connector terminal 34 and body ground.
Refer to ªTRANSFER CONTROL UNIT INSPECTION TABLEº, ªTROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONº,
TF-55.
OK or NG
OK©Disassemble transfer unit and check the following.
IControl valve assembly
I4WD solenoid valve
I2-4WD shift solenoid valve
IClutch piston
IClutch assembly
NG©GO TO 2.
2 CHECK CLUTCH PRESSURE SWITCH CIRCUIT
Check clutch pressure switch circuit.
Refer to ªDiagnostic Procedureº, ªCLUTCH PRESSURE SWITCHº, TF-80.
OK or NG
OK©GO TO 3.
NG©Check, repair or replace faulty parts.
3 CHECK PROCEDURES FROM THE BEGINNING AGAIN
Check again.
OK or NG
OK©INSPECTION END
NG©Recheck each connector's pin terminals for damage or loose connection.
TROUBLE DIAGNOSES FOR SYMPTOMS
Symptom 8. Tight Corner Braking Symptom
TF-108

Symptom 9. 4WD System Does Not Operate=NBTF0037SYMPTOM: The vehicle cannot be put into 4WD mode.
(Hydraulic system failure)
1 CHECK INPUT SIGNAL
With CONSULT-II
1. Select ªECU INPUT SIGNALSº in Data Monitor.
2. Read out the ON/OFF status of ªCLUTCH PRES SWº.
SMT977D
Without CONSULT-II
Check voltage between transfer control unit harness connector terminal 34 and body ground.
Refer to ªTRANSFER CONTROL UNIT INSPECTION TABLEº, ªTROUBLE DIAGNOSIS Ð GENERAL DESCRIPTIONº,
TF-55.
OK or NG
OK©1. Check transfer fluid level.
2. Disassemble transfer unit and check the following.
ITransfer motor
IMain oil pump assembly
ISub-oil pump assembly
IOil strainer
IControl valve assembly
I2-4WD shift solenoid valve
IOil filter element
ILip seal
IStrainer O-ring
IMain oil pump drive gear
ISeal ring
ID-ring
IClutch piston
IClutch assembly
NG©GO TO 2.
2 CHECK CLUTCH PRESSURE CIRCUIT
Check clutch pressure switch circuit.
Refer to ªDiagnostic Procedureº, ªCLUTCH PRESSURE SWITCHº, TF-80.
OK or NG
OK©GO TO 3.
NG©Check, repair or replace faulty parts.
GI
MA
EM
LC
EC
FE
AT
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
TROUBLE DIAGNOSES FOR SYMPTOMS
Symptom 9. 4WD System Does Not Operate
TF-109