A torque-converter complaint can involve several diagnostic routes. When the scan specifically records P0743, preserve that wording rather than shortening the enquiry to “gearbox slipping” or “converter faulty”.
The electrical distinction
Autel categorises P0743 as an electrical fault associated with torque-converter clutch control. Code reference, printed page 50. That is the scope of the code definition, not proof of a failed TCU or complete converter.
Keep symptom and code together
Describe when the warning appears, whether the gearbox still selects normally and what repair work preceded it. If a garage has already inspected the internal harness or valve body, include that report and the identities of replaced parts.
For electrical findings, record the test point, conditions and the specification used. Avoid unsupported summaries such as “all wiring good” when the actual tests can be provided. A fault that occurs only when warm should be identified as such in the assessment request.
Before removing the controller
Ask the diagnosing technician what points towards the controller rather than the surrounding circuit. Keep the original unit until the repair route and replacement requirements are agreed. Generic resistance values found online should not be transferred to an unidentified gearbox.
Contact AXION about transmission electronics with the full scan and existing measurements. Suitable postal work is agreed individually; a vehicle with loss of drive or unsafe behaviour should be recovered rather than driven to reproduce the fault.
Reviewed September 2026. Use the complete manufacturer-specific fault description and vehicle repair information.