> For the complete documentation index, see [llms.txt](https://wiki.retropilot.org/index/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.retropilot.org/index/vehicles/volkswagen-pq25-platform-retrofits/glossary.md).

# Glossary

| Term                  | Definition                             | Info                                                                                                             |
| --------------------- | -------------------------------------- | ---------------------------------------------------------------------------------------------------------------- |
| EPS                   | Electric Power Steering                | Assists steering                                                                                                 |
| HCA                   | Heading Control Assist                 | Commands sent to EPS over CAN BUS                                                                                |
| LKAS                  | Lane Keep Assist                       | Keeps your car in the lane by way of Openpilot or a factory installed system                                     |
| ODIS                  | Offboard Diagnostic Information System | Volkswagens official diagnostic tool                                                                             |
| VCP                   | VAG Can Pro                            | Aftermarket diagnostic tool, capable of flashing firmware                                                        |
| VCDS                  | VAG-COM Diagnostic Software            | Aftermarket diagnostic tool                                                                                      |
| VAG                   | Volkswagen AG                          | Automaker (VW, Audi, Skoda, Seat & more)                                                                         |
| J533 Harness          | Harness for Panda                      | Allows you to tap all the required CAN BUS messages from between the Body Control Module and the CAN BUS Gateway |
| BCM                   | Body Control Module                    | This module controls many functions in your car                                                                  |
| J533 / Canbus Gateway | CAN BUS Gateway                        | This module connects all the car's CAN bus networks in a central location and forwards messages between          |
| Poor people cars      | ​                                      | A term used by fully loaded MQB elitists to oppress the glorious PQ25 owners.                                    |


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