P0744 — Torque Converter Clutch Circuit Intermittent
P0744 is the standardized powertrain DTC for “Torque Converter Clutch Circuit Intermittent.” The code identifies the monitored condition; it does not by itself prove which part failed.
What P0744 means
P0744 is the standardized powertrain DTC for “Torque Converter Clutch Circuit Intermittent.” The code identifies the monitored condition; it does not by itself prove which part failed.
How to interpret the code wording
“Intermittent” means the signal fault is not continuously present. Preserve freeze-frame data, inspect harness movement/heat/vibration points, check terminal tension, and monitor the circuit while gently manipulating the harness when the service procedure permits.
Possible symptoms
- Shudder during lockup
- Engine stalls when coming to a stop if clutch remains applied
- Higher cruising RPM
- Transmission overheating or limp mode
Causes to test
These are diagnostic possibilities, not a statistical parts-replacement ranking. Vehicle-specific service information takes priority.
- Torque-converter clutch solenoid/hydraulic control problem
- Valve-body wear or contamination
- Low/incorrect/degraded transmission fluid
- Wiring or TCM control fault
- Torque converter clutch mechanical failure
Step-by-step diagnostic workflow
- Check fluid level/condition using the manufacturer procedure and correct fluid specification.
- Review TCC command, slip speed, gear, and fluid temperature during the event.
- Inspect electrical circuits and solenoid operation before condemning the converter.
- Follow transmission-specific hydraulic/pressure tests and TSBs.
- Perform circuit or mechanical tests specified by service information; repair the confirmed root cause.
- Clear codes only after repair, then complete an appropriate drive cycle and verify the code and symptoms do not return.
Scan data worth checking
- TCC command/duty
- TCC slip RPM
- Input and output speed
- Transmission fluid temperature
- Commanded gear
Severity and drivability
Moderate to high. A stuck-on converter clutch can stall the engine; excessive slip can overheat transmission fluid.
Stop driving and investigate immediately if there is a flashing MIL, oil-pressure warning, overheating, fuel leakage, severe misfire, major loss of power, abnormal mechanical noise, or a transmission that is slipping badly.
Common diagnostic mistakes
- Replacing the torque converter before valve-body/solenoid diagnosis
- Using the wrong transmission fluid
- Driving extensively with high slip and overheated fluid
Related generic codes
Source and accuracy notes
Generic DTC structure and standardized definitions are governed by SAE J2012/J2012DA. Actual enable criteria, thresholds, circuit pinouts, test values, software conditions, and repair procedures vary by vehicle. Use current OEM service information for the exact year/engine/calibration and check applicable manufacturer technical service bulletins. See the site methodology and primary-reference policy.