What it means
The torque converter clutch appears to remain applied when it should release. This may cause the engine to stall as the vehicle stops.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
The TCC clutch locks the engine to the transmission during some driving conditions and should release when the vehicle slows to a stop. The controller detects that the clutch remains applied when release is expected; a stuck solenoid or valve, contaminated valve body, or debris can prevent release and may stall the engine.
Common causes
Most likely first.
- TCC solenoid stuck on
- Valve body contaminated
- Carbon or debris buildup preventing free movement
Symptoms
- Engine may stall when coming to a stop
- Check engine or transmission warning light on
How to diagnose it
- Record freeze-frame data and check commanded TCC state, engine speed, vehicle speed, and related transmission codes around the stall or near-stop event.
- Inspect the TCC solenoid wiring and connectors for damage or a short that could keep the clutch commanded on.
- Check fluid level and condition and look for leaks or contamination using the manufacturer's procedure.
- Use scan data to determine whether the TCC command turns off as the vehicle slows and whether engine speed still drops as if the clutch remains engaged.
- Test the TCC solenoid and valve-body movement for sticking or contamination, then assess the converter clutch according to the manufacturer's diagnostic procedure.
Common fixes
- Repair wiring or connector faults that keep the TCC solenoid energized.
- Correct fluid level and address contamination or leaks according to the manufacturer's service procedure.
- Replace a TCC solenoid confirmed stuck or electrically faulty.
- Clean or repair a valve body that is preventing TCC release.
- Repair or replace the torque converter if testing confirms the clutch is mechanically stuck.
Can I keep driving?
Because the engine can stall as you stop, avoid driving in traffic and arrange recovery if the stalling occurs or the clutch will not release. A stall can reduce steering or braking assistance, and continued driving risks unsafe loss of power.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.