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OBD-II fault code definitions, symptoms, causes, and step-by-step diagnostics.
Standardized generic DTCTransmission

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.

Standardized generic definition
Torque Converter Clutch Circuit Intermittent
DTC category
Transmission
Diagnostic priority
Moderate to high. A stuck-on converter clutch can stall the engine; excessive slip can overheat transmission fluid.
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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.

Start with the stored data and the simplest external checks before replacing the component named in the code.

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

  1. Check fluid level/condition using the manufacturer procedure and correct fluid specification.
  2. Review TCC command, slip speed, gear, and fluid temperature during the event.
  3. Inspect electrical circuits and solenoid operation before condemning the converter.
  4. Follow transmission-specific hydraulic/pressure tests and TSBs.
  5. Perform circuit or mechanical tests specified by service information; repair the confirmed root cause.
  6. Clear codes only after repair, then complete an appropriate drive cycle and verify the code and symptoms do not return.
Preserve evidence: EPA OBD guidance emphasizes that stored DTCs and freeze-frame data are important to proper diagnosis. Save them before clearing codes.

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

P0743 — Torque Converter Clutch Circuit ElectricalP0742 — Torque Converter Clutch Circuit Stuck OnP0741 — Torque Converter Clutch Circuit Performance or Stuck OffP0740 — Torque Converter Clutch Circuit/Open

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.