P0743 Torque converter clutch circuit electrical
What P0743 means
The transmission control unit has detected a short or open in the torque converter clutch solenoid circuit. The converter may not lock up, or on some gearboxes may stay locked and stall the engine when stopping.
P0743 is a generic SAE J2012 code: it means the same on every make. The exact cause still depends on the car, so read the freeze-frame data before replacing parts.
At a glance
- Severity
- Medium
- Typical repair cost
- 150–900 €
- Workshop time
- 1.5–10 h
- Repair difficulty
- Hard
- DIY possible
- No
- Check engine light
- Yes
- Affects emissions test
- No
- Limp mode possible
- Yes
Parts and labour at an independent workshop in Europe. Main dealers charge more; the cause decides the bill, not the code.
Symptoms
- Higher revs at cruising speed
- Engine stalling when coming to a stop (if stuck on)
- Increased fuel consumption
- Limp mode on some cars
Common causes
- Failed TCC solenoid
- Damaged internal wiring harness
- Fluid-soaked or corroded gearbox connector
- Transmission control unit fault
Can I keep driving with P0743?
You can drive carefully, but have it checked within one to two weeks. If the engine stalls when stopping, get it checked sooner.
What to check first
- Inspect the gearbox connector
- Measure solenoid resistance through the connector
- Check the harness between the connector and the control unit
- Replace the solenoid or harness
Related codes
- P0741 Torque converter clutch circuit performance/stuck off
- P0740 Torque converter clutch circuit/open
- P0750 Shift solenoid A
- P0735 Gear 5 incorrect ratio
- P0734 Gear 4 incorrect ratio
- P0733 Gear 3 incorrect ratio
- P0732 Gear 2 incorrect ratio
- P0731 Gear 1 incorrect ratio
Data: TORKO fault-code catalogue, built on OBDex (CC0-1.0) and reviewed against workshop practice. Informational only — it does not replace a diagnosis by a mechanic.
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