Diagnostic Procedures with DTC - P0743 / P0740
DESCRIPTION AND OPERATION
This solenoid valve:
• Controls the oil pressure acting on the Torque Converter Clutch Control Valve (DCCV) by Pulse Width Modulation signals from the TCM during torque converter clutch control
• If the duty ratio of the torque converter clutch control solenoid valve is 100% for 4 seconds or more, the torque converter clutch control system is judged to be malfunctioning and DTC P0740 is stored in the TCM memory
TROUBLESHOOTING HINTS
| Malfunction Detection Conditions | Possible Cause | Inspection Item |
| • Ignition switch in "ON" position or engine running • TCM detects an open or short circuit in the torque converter clutch control solenoid valve circuit |
• Malfunction of torque converter clutch control solenoid valve • Malfunction (poor contact) in the connector • Malfunction of the A/T ECU |
• Open or short circuit in torque converter clutch control solenoid valve circuit • Torque converter clutch control solenoid valve |
| <SYMPTOM DESCRIPTION> • Increased fuel consumption • Poor acceleration (response) |
TROUBLESHOOTING PROCEDURE
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