Torque Converter Clutch Circuit Intermittent
The P0744 code indicates an intermittent fault in the torque converter clutch (TCC) circuit. The TCC locks the torque converter to improve fuel economy and reduce transmission heat. An intermittent signal suggests a loose connection, wiring issue, or failing solenoid that may cause the TCC to engage or disengage unexpectedly, leading to erratic shifting and potential transmission damage.
01. Most Common Causes
- Faulty torque converter clutch solenoid
- Wiring or connector issues in the TCC circuit
- Low transmission fluid level or dirty fluid
- Internal transmission mechanical failure
02. Symptoms You Will Notice
- Check Engine Light on
- Erratic shifting or shuddering during gear changes
- Poor fuel economy
- Transmission overheating
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Inspect transmission fluid level and condition; top off or replace if necessary.
Step 3: Visually check wiring and connectors to the TCC solenoid for damage or corrosion.
Step 4: Test TCC solenoid resistance and operation using a multimeter and scan tool.
Step 5: Perform a transmission pressure test to rule out internal mechanical issues.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as the intermittent TCC engagement can cause transmission overheating and potential failure. Have it diagnosed promptly.
How much does it cost to fix?▼
Repair costs vary from $150 for a simple solenoid replacement to $400 or more if internal transmission work is needed.