Page 1408 of 2493

ON BOARD DIAGNOSTIC LOGICNJAT0291S03This diagnosis monitors actual gear position by checking the torque
converter slip ratio calculated by TCM as follows:
Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from ECM
C: Gear ratio determined as gear position which TCM supposes
If the actual gear position is much lower than the position (4th)
supposed by TCM, the slip ratio will be much less than normal. In
case the ratio does not reach the specified value, TCM judges this
diagnosis malfunction.
This malfunction will be caused when shift solenoid valve B is stuck
closed.
Gear position supposed by TCM1234
In case of gear position with no malfunctions1234
In case of gear position with shift solenoid valve B stuck closed 1 2 2 1*
*: P0734 is detected.
Diagnostic trouble code Malfunction is detected when ... Check items (Possible cause)
: A/T 4TH GR FNCTN
A/T cannot be shifted to the 4th gear
position even if electrical circuit is good.+Shift solenoid valve A
+Shift solenoid valve B
+Line pressure solenoid valve
+Each clutch
+Hydraulic control circuit
: P0734
DTC P0734 A/T 4TH GEAR FUNCTIONEURO-OBD
Description (Cont'd)
AT-222
Page 1417 of 2493

SAT322GC
DescriptionNJAT0295The torque converter clutch solenoid valve is activated, with the
gear in ªD
4º, by the TCM in response to signals sent from the
vehicle speed and throttle position sensors. Lock-up piston opera-
tion will then be controlled.
Lock-up operation, however, is prohibited when A/T fluid tempera-
ture is too low.
When the accelerator pedal is depressed (less than 2/8) in lock-up
condition, the engine speed should not change abruptly. If there is
a big jump in engine speed, there is no lock-up.
CONSULT-II REFERENCE VALUE IN DATA MONITOR
MODE
NJAT0295S01Remarks: Specification data are reference values.
Monitor item Condition Specification
Torque converter clutch solenoid valve
dutyLock-up ªOFFº
¯
Lock-up ªONºApproximately 4%
¯
Approximately 94%
TCM TERMINALS AND REFERENCE VALUENJAT0295S02Remarks: Specification data are reference values.
Terminal
No.Wire color Item ConditionJudgement
standard
3 GY/RTorque converter
clutch solenoid
valve
When A/T performs lock-up. 8 - 15V
When A/T does not perform lock-
up.1V or less
ON BOARD DIAGNOSIS LOGICNJAT0295S03
Diagnostic trouble code Malfunction is detected when ... Check items (Possible cause)
: TCC SOLENOID/CIRC TCM detects an improper voltage drop
when it tries to operate the solenoid
valve.+Harness or connectors
(The solenoid circuit is open or shorted.)
+T/C clutch solenoid valve
: P0740
DTC P0740 TORQUE CONVERTER CLUTCH
SOLENOID VALVE
EURO-OBD
Description
AT-231
Page 1418 of 2493
SAT014K
SAT020K
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION
PROCEDURE
NJAT0295S04NOTE:
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.
2) Select ªDATA MONITORº mode for ªENGINEº with CON-
SULT-II and wait at least 1 second.
With GST
Follow the procedure ªWith CONSULT-IIº.
DTC P0740 TORQUE CONVERTER CLUTCH
SOLENOID VALVE
EURO-OBD
Description (Cont'd)
AT-232
Page 1419 of 2493
Wiring Diagram Ð AT Ð TCVNJAT0296
YAT239
DTC P0740 TORQUE CONVERTER CLUTCH
SOLENOID VALVE
EURO-OBD
Wiring Diagram Ð AT Ð TCV
AT-233
Page 1420 of 2493
Diagnostic ProcedureNJAT0297
1 CHECK VALVE RESISTANCE
1. Turn ignition switch to ªOFFº position.
2. Disconnect terminal cord assembly connector in engine compartment.
3. Check resistance between terminal 5 and ground.
Resistance:
5-20W
SAT889JB
OK or NG
OK©GO TO 2.
NG©1. Remove oil pan. Refer to AT-343.
2. Check the following items:
+Torque converter clutch solenoid valve
Refer to ªComponent Inspectionº, AT-236.
+Harness of terminal cord assembly for short or open
DTC P0740 TORQUE CONVERTER CLUTCH
SOLENOID VALVE
EURO-OBD
Diagnostic Procedure
AT-234
Page 1421 of 2493
2 CHECK POWER SOURCE CIRCUIT
1. Turn ignition switch to ªOFFº position.
2. Disconnect TCM harness connector.
3. Check continuity between terminal 5 and TCM harness connector terminal 3.
Continuity should exist.
SAT890JB
If OK, check harness for short to ground and short to power.
4. Reinstall any part removed.
OK or NG
OK©GO TO 3.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
3 CHECK DTC
Perform Diagnostic Trouble Code (DTC) confirmation procedure, AT-232.
OK or NG
OK©INSPECTION END
NG©1. Perform TCM input/output signal inspection.
2. If NG, recheck TCM pin terminals for damage or loose connection with harness con-
nector.
DTC P0740 TORQUE CONVERTER CLUTCH
SOLENOID VALVE
EURO-OBD
Diagnostic Procedure (Cont'd)
AT-235
Page 1422 of 2493
SAT053KA
Component InspectionNJAT0298TORQUE CONVERTER CLUTCH SOLENOID VALVENJAT0298S01+For removal, refer to AT-343.
Resistance CheckNJAT0298S0101+Check resistance between two terminals.
Solenoid valve Terminal No.Resistance
(Approx.)
Torque converter
clutch solenoid
valve5 Ground 5 - 20W
SAT054KA
Operation CheckNJAT0298S0102+Check solenoid valve by listening for its operating sound while
applying battery voltage to the terminal and ground.
DTC P0740 TORQUE CONVERTER CLUTCH
SOLENOID VALVE
EURO-OBD
Component Inspection
AT-236
Page 1483 of 2493

6. Vehicle Does Not Creep Backward In ªRº
Position
=NJAT0336SYMPTOM:
Vehicle does not creep backward when selecting ªRº position.
1 CHECK A/T FLUID LEVEL
Check A/T fluid level again.
SAT638A
OK or NG
OK©GO TO 2.
NG©Refill ATF.
2 CHECK STALL TEST
Check stall revolution with selector lever in ª1º and ªRº positions.
Refer to ªSTALL TESTº, AT-78.
SAT493G
OK or NG
OK©GO TO 3.
OK in ª1º position, NG in
ªRº position©1. Remove control valve assembly. Refer to ªON-VEHICLE SERVICEº, AT-343.
2. Check the following items:
+Valves to control line pressure (Pressure regulator valve, pressure modifier valve, pilot
valve and pilot filter)
+Line pressure solenoid valve (AT-174: Except for Euro-OBD/AT-237: Euro-OBD)
3. Disassemble A/T.
4. Check the following items:
+Oil pump assembly
+Torque converter
+Reverse clutch assembly
+High clutch assembly
+Low & reverse brake assembly
+Low one-way clutch
NG in both ª1º and ªRº
positions©GO TO 6.
TROUBLE DIAGNOSES FOR SYMPTOMS
6. Vehicle Does Not Creep Backward In ªRº Position
AT-297