DTC P0740-15: Torque Converter Clutch Circuit Short to Battery or Open [11/2021 - ]: Procedure
WARNING: This page is about a different car, the 2025 Lexus NX 350, 2024 Lexus NX 350, 2023 Lexus NX 350, and 2022 Lexus NX 350. However, it is still accessible from the selected car via links, so may be relevant.
- INSPECT TRANSMISSION WIRE (SOLENOID (SL) VALVE)
- Disconnect the B39 transmission wire connector.
*a Component without harness connected
(Transmission Wire) - Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition B39-13 (SL) - Body ground 20°C (68°F) 11 to 15 Ω B39-13 (SL) - Other terminals Always 10 kΩ or higher - Connect the B39 transmission wire connector.
Result
Proceed to OK NG
Result:
NG
See step 4
Result:
OK
See step 2
- Disconnect the B39 transmission wire connector.
- CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM)
- Disconnect the B51 ECM connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition B51-42 (SL) - Body ground 20°C (68°F) 11 to 15 Ω B51-42 (SL) - Other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (TRANSMISSION WIRE - ECM)
Result:
OK
See step 3
- REPLACE ECM
Refer to REMOVAL [11/2021 - ]
Result
Proceed to NEXT Result:
NEXT
PERFORM REGISTRATION. Refer to REGISTRATION [11/2021 - ]
- INSPECT SOLENOID (SL) VALVE
- Remove the solenoid (SL) valve.
*1 Solenoid (SL) Valve Refer to DISASSEMBLY [11/2021 - ]
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Solenoid (SL) valve connector terminal - Solenoid (SL) valve body 20°C (68°F) 11 to 15 Ω - Connect a positive (+) lead from the battery to the terminal of the solenoid valve connector, and a negative (-) lead to the solenoid body. Check that the valve moves and makes an operating sound.
OK
Valve moves and makes an operating sound.
Result
Proceed to OK NG
Result:
OK
REPAIR OR REPLACE TRANSMISSION WIRE. Refer to REMOVAL [11/2021 - ]
Result:
NG
REPLACE SOLENOID (SL) VALVE. Refer to REMOVAL [11/2021 - ]
- Remove the solenoid (SL) valve.