P0743
Torque Converter Clutch Circuit Electrical
Transmission — torque converter
Generic OBD-II
Medium
What it means
P0743 means the transmission control module found an electrical fault in the circuit that operates the torque converter clutch (TCC). With the TCC not locking up properly, you may feel shudder or slipping at cruising speed and see higher engine RPM on the highway. The engine still starts and runs, but the transmission can run hotter until it is repaired.
Medium
Can I keep driving? Usually fine for short trips — the car still drives, but you may feel slipping or shudder and higher highway RPM, and the transmission can run hotter, so have it checked before long drives.
Common symptoms
What you'll notice
- Check-engine light on
- Torque converter shudder or slipping, especially at cruising speed
- Higher-than-normal engine RPM on the highway
- Harsh or delayed shifting
- Slightly reduced fuel economy
Common causes
Most likely first
- Failed torque converter clutch (TCC) solenoidLikely
- Damaged, shorted, or corroded wiring or connector in the TCC circuitCommon
- Poor ground or loose connector at the transmissionCommon
- Internal transmission fault affecting the TCCLess often
- Failed transmission control module (TCM) — least commonLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and confirm the code with a scan tool.
- Inspect the TCC solenoid wiring and connector at the transmission for damage or corrosion.
- Measure the solenoid resistance against spec and test its control circuit for opens/shorts.
- Replace the TCC solenoid if it is out of spec.
- If wiring and solenoid check out, have the transmission/TCM diagnosed. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0743?+
Short trips are usually fine, but persistent TCC slipping raises transmission temperature — avoid long highway drives until it is fixed.
Can I just clear P0743?+
You can, but it returns until the solenoid or wiring fault in the TCC circuit is repaired.
Related codes
Often seen with P0743
Read & clear P0743 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX