2001 INFINITI QX4 ignition

Gear position supposed by TCM 1 2 3 4
In case of gear position with no malfunctions 1 2 3 4
In case of gear position with shift solenoid valve B stuck closed 1 2 2 1*
*: P0744 is detected.
Diagnostic trouble code Malfunction is detected when ... Check item (Possible cause)
: A/T TCC S/V FNCTN
A/T cannot perform lock-up even if elec-
trical circuit is good.ILine pressure solenoid valve
ITorque converter clutch solenoid valve
IEach clutch
IHydraulic control circuit
: P0744
SAT014K
SAT971J
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NBAT0054S01CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.
With CONSULT-II
1) Start engine and select ªDATA MONITORº mode for ªA/Tº with
CONSULT-II.
2) Make sure that output voltage of A/T fluid temperature sensor
is within the range below.
FLUID TEMP SEN: 0.4 - 1.5V
If out of range, drive the vehicle to decrease the voltage (warm
up the fluid) or stop engine to increase the voltage (cool down
the fluid).
3) Select ªTCC S/V FNCTN P0744º of ªDTC WORK SUPPORTº
mode for ªA/Tº with CONSULT-II and touch ªSTARTº.
SAT021J
4) Accelerate vehicle to more than 67 to 100 km/h (42 to 62 MPH)
and maintain the following condition continuously until ªTEST-
INGº has turned to ªCOMPLETEDº. (It will take approximately
30 seconds after ªTESTINGº shows.)
THROTTLE POSI: 1.0/8 - 2.0/8 (at all times during step 4)
Selector lever: D position (OD ªONº)
TCC S/V DUTY: More than 94%
VHCL/S SE´A/T: Constant speed of more than 67 to 100
km/h (42 to 62 MPH)
ICheck that ªGEARº shows ª4º.
IFor shift schedule, refer to SDS, AT-356.
DTC P0744 IMPROPER LOCK-UP OPERATION
Description (Cont'd)
AT-154

SAT014K
SAT020K
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NBAT0057S01NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
for ªENGINEº with CONSULT-II.
2) Depress accelerator pedal completely and wait at least 1 sec-
ond.
With GST
Follow the procedure ªWith CONSULT-IIº.
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P0745 LINE PRESSURE SOLENOID VALVE
Description (Cont'd)
AT-163

Diagnostic ProcedureNBAT0058
1 CHECK VALVE RESISTANCE
1. Turn ignition switch to ªOFFº position.
2. Disconnect terminal cord assembly connector on the right side of transfer assembly.
3. Check resistance between terminal 6 and ground.
SAT162J
Is resistance approx. 2.5 - 5W?
Ye s©GO TO 3.
No©GO TO 2.
2 CHECK VALVE OPERATION
1. Remove control valve assembly.
Refer to AT-273.
2. Check the following items:
ILine pressure solenoid valve
Refer to ªComponent Inspectionº, AT-167.
IHarness of terminal cord assembly for short or open
OK or NG
OK©GO TO 3.
NG©Repair or replace damaged parts.
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P0745 LINE PRESSURE SOLENOID VALVE
Diagnostic Procedure
AT-165

3 CHECK POWER SOURCE AND DROPPING RESISTOR CIRCUIT
1. Turn ignition switch to ªOFFº position.
2. Disconnect TCM harness connector.
3. Check resistance between terminal 6 and TCM harness connector terminal 2.
SAT522J
Is resistance approx. 11.2 - 12.8W?
Ye s©GO TO 5.
No©GO TO 4.
4 DETECT MALFUNCTIONING ITEM
Check the following items:
IDropping resistor
Refer to ªComponent Inspectionº, AT-167.
IHarness for short or open between TCM terminal 2 and terminal cord assembly (Main harness)
OK or NG
OK©GO TO 5.
NG©Repair or replace damaged parts.
5 CHECK POWER SOURCE CIRCUIT
1. Turn ignition switch to ªOFFº position.
2. Check continuity between terminal 6 and TCM harness connector terminal 1. Refer to wiring diagram Ð AT Ð LPSV.
Continuity should exist.
If OK, check harness for short to ground or to power.
3. Reinstall any part removed.
Ye s©GO TO 6.
No©Repair or replace harness between TCM terminal 1 and terminal cord assembly.
6 CHECK DTC
Perform Diagnostic Trouble Code (DTC) confirmation procedure, AT-163.
OK or NG
OK©INSPECTION END
NG©GO TO 7.
DTC P0745 LINE PRESSURE SOLENOID VALVE
Diagnostic Procedure (Cont'd)
AT-166

SAT341H
DescriptionNBAT0060Shift solenoid valves A and B are turned ªONº or ªOFFº by the TCM
in response to signals sent from the PNP switch, vehicle speed and
throttle position sensors. Gears will then be shifted to the optimum
position.
Gear position1234
Shift solenoid valve A ON (Closed) OFF (Open) OFF (Open) ON (Closed)
Shift solenoid valve B ON (Closed) ON (Closed) OFF (Open) OFF (Open)
TCM TERMINALS AND REFERENCE VALUENBAT0060S02Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
(Approx.)
11 L/WShift solenoid
valve A
When shift solenoid valve A operates.
(When driving in ªD
1ºorªD4º.)Battery volt-
age
When shift solenoid valve A does not operate.
(When driving in ªD
2ºorªD3º.)0V
ON BOARD DIAGNOSIS LOGICNBAT0060S03
Diagnostic trouble code Malfunction is detected when ... Check item (Possible cause)
: SFT SOL A/CIRC TCM detects an improper voltage drop
when it tires to operate the solenoid
valve.IHarness or connectors
(The solenoid circuit is open or shorted.)
IShift solenoid valve A
: P0750
SAT014K
SAT020K
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NBAT0060S01CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
for ªENGINEº with CONSULT-II.
2) Start engine.
3) Drive vehicle in ªDº position and allow the transmission to shift
ª1º,ª2º (ªGEARº).
With GST
Follow the procedure ªWith CONSULT-IIº.
DTC P0750 SHIFT SOLENOID VALVE A
Description
AT-168

Diagnostic ProcedureNBAT0061
1 CHECK VALVE RESISTANCE
1. Turn ignition switch to ªOFFº position.
2. Disconnect terminal cord assembly connector on the right side of transfer assembly.
3. Check resistance between terminal 3 and ground.
SAT164J
Is resistance approx. 20 - 40W?
Ye s©GO TO 3.
No©GO TO 2.
2 CHECK VALVE OPERATION
1. Remove control valve assembly.
Refer to AT-273.
2. Check the following items:
IShift solenoid valve A
Refer to ªComponent Inspectionº, AT-171.
IHarness of terminal cord assembly for short or open
OK or NG
OK©GO TO 3.
NG©Repair or replace damaged parts.
3 CHECK POWER SOURCE CIRCUIT
1. Turn ignition switch to ªOFFº position.
2. Disconnect TCM harness connector.
3. Check resistance between terminal 3 and TCM harness connector terminal 11. Refer to wiring diagram Ð AT Ð
SSV/A.
Continuity should exist.
If OK, check harness for short to ground and short to power.
4. Reinstall any part removed.
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 DTC
Perform Diagnostic Trouble Code (DTC) confirmation procedure, AT-168.
OK or NG
OK©INSPECTION END
NG©GO TO 5.
DTC P0750 SHIFT SOLENOID VALVE A
Diagnostic Procedure
AT-170

SAT341H
DescriptionNBAT0063Shift solenoid valves A and B are turned ªONº or ªOFFº by the TCM
in response to signals sent from the PNP switch, vehicle speed and
throttle position sensors. Gears will then be shifted to the optimum
position.
Gear position1234
Shift solenoid valve A ON (Closed) OFF (Open) OFF (Open) ON (Closed)
Shift solenoid valve B ON (Closed) ON (Closed) OFF (Open) OFF (Open)
TCM TERMINALS AND REFERENCE VALUENBAT0063S02Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
(Approx.)
12 L/RShift solenoid
valve B
When shift solenoid valve B operates.
(When driving in ªD
1ºorªD2º.)Battery volt-
age
When shift solenoid valve B does not operate.
(When driving in ªD
3ºorªD4º.)0V
ON BOARD DIAGNOSIS LOGICNBAT0063S03
Diagnostic trouble code Malfunction is detected when ... Check item (Possible cause)
: SFT SOL B/CIRC TCM detects an improper voltage drop
when it tires to operate the solenoid
valve.IHarness or connectors
(The solenoid circuit is open or shorted.)
IShift solenoid valve B
: P0755
SAT014K
SAT020K
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NBAT0063S01CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If ªDIAGNOSTIC TROUBLE CODE CONFIRMATION PROCE-
DUREº has been previously conducted, always turn ignition
switch ªOFFº and wait at least 5 seconds before conducting
the next test.
After the repair, perform the following procedure to confirm the
malfunction is eliminated.
With CONSULT-II
1) Turn ignition switch ªONº and select ªDATA MONITORº mode
for ªENGINEº with CONSULT-II.
2) Drive vehicle in ªDº position and allow the transmission to shift
1,2,3 (ªGEARº).
With GST
Follow the procedure ªWith CONSULT-IIº.
DTC P0755 SHIFT SOLENOID VALVE B
Description
AT-172

Diagnostic ProcedureNBAT0064
1 CHECK VALVE RESISTANCE
1. Turn ignition switch to ªOFFº position.
2. Disconnect terminal cord assembly connector on the right side of transfer assembly.
3. Check resistance between terminal 2 and ground.
SAT166J
Is resistance approx. 20 - 40W?
Ye s©GO TO 3.
No©GO TO 2.
2 CHECK VALVE OPERATION
1. Remove control valve assembly.
Refer to AT-273.
2. Check the following items:
IShift solenoid valve B
Refer to ªComponent Inspectionº, AT-175.
IHarness of terminal cord assembly for short or open
OK or NG
OK©GO TO 3.
NG©Repair or replace damaged parts.
3 CHECK POWER SOURCE CIRCUIT
1. Turn ignition switch to ªOFFº position.
2. Disconnect TCM harness connector.
3. Check resistance between terminal 2 and TCM harness connector terminal 12. Refer to wiring diagram Ð AT Ð
SSV/B.
Continuity should exist.
If OK, check harness for short to ground and short to power.
4. Reinstall any part removed.
Is resistance approx. 0W?
Ye s©GO TO 4.
No©Repair open circuit or short to ground or short to power in harness or connectors.
4 CHECK DTC
Perform Diagnostic Trouble Code (DTC) confirmation procedure, AT-172.
OK or NG
OK©INSPECTION END
NG©GO TO 5.
DTC P0755 SHIFT SOLENOID VALVE B
Diagnostic Procedure
AT-174