What the table controls
The Lock Duty Cycle table sets the duty sent to the torque converter lockup solenoid while the ECU is commanding the converter to lock. A good lockup isn't an on/off event. The best result comes from feeding pressure in progressively, so the lockup clutch engages gently instead of slamming on.
In the Haltech example setup, lower duty means more fluid pressure to the lockup clutch. So the curve starts at 0% duty for full flow, which quickly takes up the clearance until the clutch is about to bite. Duty then rises to ease the pressure as the clutch starts to grab, softening engagement, and finally drops to a very low duty to hold the clutch fully applied with as little slip as possible. Check how your transmission's solenoid responds before assuming the same direction.
Where to start
Don't build this curve from scratch. Import a Haltech transmission base map for your gearbox as a starting point, and check whether the workshop manual for your transmission lists a recommended lockup curve. Then refine from logs: watch engine rpm against converter output speed during lockup. A clean lockup shows the gap closing smoothly. A sudden drop means engagement is too harsh, and a gap that never closes means the clutch is slipping.
When lockup happens is set by the lock point and unlock point tables. For the full picture see torque converter control, or ask us for help with your transmission.
