Vehicle configuration and longitudinal control
Longitudinal control means openpilot generates acceleration and deceleration requests directly. Distinguish this from a configuration where steering is assisted but stock SCC controls speed.
Terms
| Term | Meaning | Related settings |
|---|---|---|
| Lateral control | Steering and path following | Steering tuning and lane changes |
| Longitudinal control | Acceleration, deceleration and stopping | Following gap, acceleration planning and controller |
| Stock SCC | Vehicle SCC controls longitudinal motion | Set speed may be adjusted through button messages |
| Vision / radar | Inputs for lead-vehicle detection | Input selection and control authority are separate |
Changing radar settings does not automatically enable longitudinal control. Longitudinal control does not mean braking for every object.
Connection categories in the current README
| Configuration | Connection guidance |
|---|---|
| Conventional CAN | Genuine comma harness, camera connection |
| Conventional CAN-FD | Genuine comma harness, camera connection |
| CAN-FD HDA2 with ADAS module | Separate harness, ADAS-module connection |
On supported HDA2 configurations, connecting at the ADAS module allows carrotpilot to generate acceleration and deceleration directly. Support can differ with model year, ECU, camera and wiring, even for the same model name.
Record before installation
Vehicle / model year / engine·HEV·EV / HDA configuration / harness type / connection point / device
Check vehicle selection, actual CAN validity, errors and the vehicle-specific interface together. An old claim about “all ccNC vehicles” or a connector pin count is not enough to establish support.
Wiring references
These four pages preserve historical diagrams. Compare them with the service wiring diagram and harness specification for your exact vehicle. Software code alone cannot establish whether a pinout is suitable.
What changes with longitudinal control?
Following gap, speed-dependent acceleration limits and lead response become meaningful planner settings. Some have no direct effect with stock SCC. Stock AEB and FCW cannot be assumed to remain intact in every modified configuration.
Next: Installation → Cruise and following gap.
Source reference
Reference checked 2026-10-30 · carrot-wip · 10bf0a56.
README.md · opendbc_repo/opendbc/car/hyundai/interface.py · docs/user/ko/cruise-gap.md
The development branch continues to change. Check your device’s branch, commit and current settings together.