P1740

DTC P1740 LOCK-UP SELECT SOLENOID VALVE CIRCUIT





Description
- The lock-up select solenoid valve controls lock-up clutch pressure or forward clutch pressure (reverse brake pressure).
- When controlling lock-up clutch, the valve is turned OFF. When controlling forward clutch, it is turned ON.




CONSULT-III Reference Value









On Board Diagnosis Logic
- This is an OBD-II self-diagnostic item.
- Diagnostic trouble code "P1740 LU-SLCT SOL/CIRC" with CONSULT-III is detected under the following conditions.
- When TCM compares target value with monitor value and detects an irregularity.




Possible Cause
- Lock-up select solenoid valve
- Harness or connectors
(Solenoid circuit is open or shorted.)




DTC Confirmation Procedure

CAUTION:
Always drive vehicle at a safe speed.

NOTE:
If "DTC Confirmation Procedure" has been previously performed, always turn ignition switch OFF and wait at least 10 seconds before performing the next test.
After the repair, touch "ERASE" on "SELF-DIAG RESULTS" and then perform the following procedure to confirm the malfunction is eliminated.

WITH CONSULT-III
1. Turn ignition switch ON.
2. Select "DATA MONITOR" mode for "TRANSMISSION" with CONSULT-III.
3. Start engine and maintain the following conditions for at least 5 consecutive seconds.
RANGE: "D" position and "N" position
(At each time, wait for 5 seconds.)
4. If DTC is detected, go to "Diagnosis Procedure".

WITH GST
Follow the procedure "WITH CONSULT-III".




Wiring Diagram - CVT - L/USSV






TCM TERMINALS AND REFERENCE VALUES
Refer to TCM Input/Output Signal Reference Value.




Diagnosis Procedure
1. CHECK INPUT SIGNAL
With CONSULT-III
1. Turn ignition switch ON.
2. Select "SELECTION FROM MENU" in "DATA MONITOR" mode for "TRANSMISSION" with CONSULT-III.
3. Read out the value of "LUSEL SOL OUT" and "LUSEL SOL MON".





Without CONSULT-III
1. Turn ignition switch ON.
2. Check voltage between TCM connector terminal and ground.





3. Turn ignition switch OFF.
4. Disconnect the TCM connector.
5. Check if there is continuity between connector terminal and ground.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2.CHECK LOCK-UP SELECT SOLENOID VALVE CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect TCM connector.





3. Check resistance between TCM connector terminal and ground.





OK or NG
OK >> GO TO 5.
NG >> GO TO 3.
3.CHECK VALVE RESISTANCE
1. Turn ignition switch OFF.
2. Disconnect CVT unit harness connector.





3. Check resistance between CVT unit harness connector terminal and ground.





OK or NG
OK >> GO TO 4.
NG >> Replace the transaxle assembly. Refer to .
4.CHECK HARNESS BETWEEN TCM AND LOCK-UP SELECT SOLENOID VALVE
1. Turn ignition switch OFF.
2. Disconnect TCM connector (A) and CVT harness connector (B).





3. Check continuity between TCM connector (A) terminal and CVT unit harness connector (B) terminal.





4. If OK, check harness for short to ground and short to power.
5. Reinstall any part removed.
OK or NG
OK >> GO TO 5.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
5.CHECK DTC
Perform "DTC Confirmation Procedure".
OK or NG
OK >> INSPECTION END
NG >> GO TO 6.
6.CHECK TCM
1. Check TCM input/output signals. Refer to TCM Input/Output Signal Reference Value.
2. If NG, re-check TCM pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> INSPECTION END
NG >> 1. Repair or replace damaged parts.
2. Replace TCM. Refer to Service After Replacing TCM And Transaxle Assembly.




Component Inspection

LOCK-UP SELECT SOLENOID VALVE
1. Turn ignition switch OFF.
2. Disconnect CVT unit harness connector.





3. Check resistance between CVT unit harness connector terminal and ground.





4. If NG, replace the transaxle assembly. Refer to .