P0743: Torque converter clutch circuit electrical fault
The control unit sees an electrical fault in the torque converter clutch solenoid circuit: a wire, a connector or the solenoid itself.
| Code | P0743 |
|---|---|
| System | Engine and transmission |
| Group | P07xx, Transmission |
| Type | Generic: it means the same on every make |
| Can you keep driving? | With care |
What P0743 means
The torque converter links the engine to the automatic gearbox. At a steady speed an internal clutch locks it so no power or fuel is wasted, and that clutch is worked by a solenoid controlled by the ECU. The control unit measures an impossible voltage or current in the circuit of the torque converter clutch solenoid, typical of a broken wire, a short or a burnt-out coil.
Most common causes
- Connector for the torque converter clutch solenoid loose, corroded or with fluid inside
- Wire broken, bare or rubbing against the gearbox
- Gearbox pass-through connector (where the wiring enters) leaking or with loose pins
- The torque converter clutch solenoid with an open or shorted coil
- Fuse or power supply to the circuit
- Transmission control unit (uncommon)
Symptoms
- Engine warning light on
- Higher revs and fuel use at a steady speed
- Judder at low speed or when stopping
- On some cars the gearbox goes into limp mode
Can you drive with P0743?
With care You can keep driving gently, but get it looked at soon: the gearbox fluid runs hotter and the torque converter can end up damaged.
How to check it
With the ignition off, check the gearbox connector is fully seated, with no green corrosion or fluid inside. If the code comes back straight after clearing, a broken wire or the solenoid coil is the likely culprit.
How to read and clear P0743 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P0743 with this same explanation and whether it’s confirmed, pending or permanent.
This code is usually stored by the gearbox control unit. With Free you read it for nothing with its short description, because Free reads every control unit; with Pro you also get the full explanation, how the car was running when it was logged and clearing.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before the ITV. It’s all in how to read and clear fault codes and in the ITV and OBD.
Similar codes
- P0735 Incorrect gear ratio in fifth gear
- P0740 Torque converter clutch circuit fault
- P0741 Torque converter clutch poor performance or not engaging
- P0742 Torque converter clutch stuck engaged
- P0744 Torque converter clutch circuit intermittent fault
- P0745 Gearbox pressure control solenoid fault
- P0746 Pressure control solenoid poor performance or stuck off
- P0747 Pressure control solenoid stuck on
- P0700 Transmission control system: fault detected
- P0701 Transmission control system: range/performance
- P0702 Transmission control system: electrical fault
- P0703 Torque converter/brake switch B: circuit fault
P0743 is a generic code, so it means the same on any make, for example on BMW, Citroën, Ford, Mercedes-Benz, Renault, Volvo. See what Final OBD does on your car in makes and models.
What does code P0743 mean?
The torque converter links the engine to the automatic gearbox. At a steady speed an internal clutch locks it so no power or fuel is wasted, and that clutch is worked by a solenoid controlled by the ECU. The control unit measures an impossible voltage or current in the circuit of the torque converter clutch solenoid, typical of a broken wire, a short or a burnt-out coil.
Can you drive with P0743?
You can keep driving gently, but get it looked at soon: the gearbox fluid runs hotter and the torque converter can end up damaged.
How do you clear P0743?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P0743 comes back.
Read it on your car
Final OBD reads the faults of every control unit for free, including each make’s own codes, and with Pro explains each one in plain English. Free clears engine faults at no cost.
Coming soon
Mid to late October 2026
If you want to try it in your car before anyone else, send us your email and we will add you as a tester.
info@finalobd.com