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Wiring Diagram Ð AT Ð TCCSIGNBAT0195
MAT913A
DTC P0744 IMPROPER LOCK-UP OPERATION
Wiring Diagram Ð AT Ð TCCSIG
AT-156
Page 162 of 2395
Diagnostic Procedure=NBAT0055
1 CHECK SHIFT UP (D3TO D4)
During ªCruise test þ Part 1º, AT-71.
Does A/T shift from D
3to D4at the specified speed?
SAT988H
YesorNo
Ye s©IGO TO 10.
IAnd check for proper lock-up.
No©GO TO 2.
2 CHECK LINE PRESSURE
Perform line pressure test. Refer to AT-62.
OK or NG
OK©GO TO 3.
NG©GO TO 6.
3 CHECK CONTROL VALVE
1. Disassemble control valve assembly. Refer to AT-301.
2. Check to ensure that:
IValve, sleeve and plug slide along valve bore under their own weight.
IValve, sleeve and plug are free from burrs, dents and scratches.
IControl valve springs are free from damage, deformation and fatigue.
IHydraulic line is free from obstacles.
SAT367H
OK or NG
OK©GO TO 4.
NG©Repair control valve.
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P0744 IMPROPER LOCK-UP OPERATION
Diagnostic Procedure
AT-157
Page 163 of 2395
4 CHECK SHIFT UP (D3TO D4)
Does A/T shift from D3to D4at the specified speed?
YesorNo
Ye s©GO TO 5.
No©Check control valve again. Repair or replace control valve assembly.
5 CHECK DTC
Perform Diagnostic Trouble Code (DTC) confirmation procedure, AT-154.
OK or NG
OK©INSPECTION END
NG©IGO TO 10.
IAnd check for proper lock-up.
6 CHECK LINE PRESSURE SOLENOID VALVE
1. Remove control valve assembly. Refer to AT-273.
2. Check line pressure solenoid valve operation. Refer to AT-161.
SAT158J
OK or NG
OK©GO TO 7.
NG©Replace solenoid valve assembly.
DTC P0744 IMPROPER LOCK-UP OPERATION
Diagnostic Procedure (Cont'd)
AT-158
Page 164 of 2395

7 CHECK CONTROL VALVE
1. Disassemble control valve assembly. Refer to AT-301.
2. Check line pressure circuit valves for sticking.
IPressure regulator valve
IPilot valve
IPressure modifier valve
SAT367H
OK or NG
OK©GO TO 8.
NG©Repair control valve.
8 CHECK SHIFT UP (D3TO D4)
Does A/T shift from D3to D4at the specified speed?
YesorNo
Ye s©GO TO 9.
No©Check control valve again. Repair or replace control valve assembly.
9 CHECK DTC
Perform Diagnostic Trouble Code (DTC) confirmation procedure, AT-154.
OK or NG
OK©INSPECTION END
NG©IGO TO 10.
IAnd check for proper lock-up.
10 CHECK LOCK-UP CONDITION
During ªCruise test þ Part 1º, AT-71.
Does A/T perform lock-up at the specified speed?
YesorNo
Ye s©Perform ªCruise test þ Part 1º again and return to the start point of this flow chart.
No©GO TO 11.
11 CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE
1. Remove control valve assembly. Refer to AT-273.
2. Check torque converter clutch solenoid valve operation.
Refer to AT-161.
OK or NG
OK©GO TO 12.
NG©Replace solenoid valve assembly.
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P0744 IMPROPER LOCK-UP OPERATION
Diagnostic Procedure (Cont'd)
AT-159
Page 165 of 2395
12 CHECK CONTROL VALVE
1. Disassemble control valve assembly. Refer to AT-301.
2. Check control valves for sticking.
ITorque converter clutch control valve
ITorque converter clutch relief valve
SAT367H
OK or NG
OK©GO TO 13.
NG©Repair control valve
13 CHECK LOCK-UP CONDITION
Does A/T perform lock-up at the specified speed?
YesorNo
Ye s©GO TO 14.
No©Check control valve again. Repair or replace control valve assembly.
14 CHECK DTC
Perform Diagnostic Trouble Code (DTC) confirmation procedure, AT-154.
OK or NG
OK©INSPECTION END
NG©Perform ªCruise test Ð Part 1º again and return to the start point of this flow chart.
DTC P0744 IMPROPER LOCK-UP OPERATION
Diagnostic Procedure (Cont'd)
AT-160
Page 166 of 2395
SAT159J
Component InspectionNBAT0056SOLENOID VALVESNBAT0056S01IFor removal, refer to AT-273.
Resistance CheckNBAT0056S0101ICheck resistance between terminals (6 or 7) and ground.
Solenoid valve Terminal No. Resistance (Approx.)
Line pressure solenoid valve 6
Ground2.5-5W
Torque converter clutch
solenoid valve7 10-20W
SAT158J
Operation CheckNBAT0056S0102ICheck solenoid valve by listening for its operating sound while
applying battery voltage to the terminals (6 or 7) and ground.
GI
MA
EM
LC
EC
FE
TF
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
DTC P0744 IMPROPER LOCK-UP OPERATION
Component Inspection
AT-161
Page 167 of 2395

SAT341H
DescriptionNBAT0057The line pressure solenoid valve regulates the oil pump discharge
pressure to suit the driving condition in response to a signal sent
from the TCM.
The line pressure duty cycle value is not consistent when the
closed throttle position switch is ªONº. To confirm the line
pressure duty cycle at low pressure, the accelerator (throttle)
should be open until the closed throttle position switch is
ªOFFº.
CONSULT-II REFERENCE VALUE IN DATA MONITOR
MODE
NBAT0057S02Remarks: Specification data are reference values.
Monitor item Condition Specification
Line pressure solenoid
valve dutySmall throttle opening (Low line pressure)
"
Large throttle opening (High line pressure)Approximately 24%
"
Approximately 95%
NOTE:
The line pressure duty cycle value is not consistent when the closed throttle position switch is ªONº. To confirm the line pressure duty
cycle at low pressure, the accelerator (throttle) should be open until the closed throttle position switch is ªOFFº.
TCM TERMINALS AND REFERENCE VALUENBAT0057S03Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
(Approx.)
1GYLine pressure
solenoid valve
When releasing accelerator pedal after warm-
ing up engine.1.5 - 3.0V
When depressing accelerator pedal fully after
warming up engine.0V
2 BR/YLine pressure
solenoid valve
(with dropping
resistor)When releasing accelerator pedal after warm-
ing up engine.5 - 14V
When depressing accelerator pedal fully after
warming up engine.0V
ON BOARD DIAGNOSIS LOGICNBAT0057S04
Diagnostic trouble code Malfunction is detected when ... Check item (Possible cause)
: L/PRESS SOL/CIRCTCM detects an improper voltage drop
when it tries to operate the solenoid
valve.IHarness or connectors
(The solenoid circuit is open or shorted.)
ILine pressure solenoid valve
: P0745
DTC P0745 LINE PRESSURE SOLENOID VALVE
Description
AT-162
Page 168 of 2395
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