Enhancing Rivian R1T with Comma 3X: A Hands-Free Driving Experience
The allure of autonomous driving has captivated many electric vehicle (EV) owners, particularly those in the Rivian community. A $1,500 device known as the Comma 3X promises to transform the Rivian R1T into a semi-autonomous machine. But does it live up to expectations?
The Comma 3X Experience
MrMusAddict from the Rivian Forum shared a detailed account of installing and using the Comma 3X. The device offers several features out of the box with its default software, including drive-line detection, lane centering, auto steer, hands-free driving on any road, lane changes, and dashcam functionality. While it’s designed to be an improved version of Rivian’s Driver+, it comes with geographic restrictions.

Performance and Limitations
The Comma 3X excels in drive-line detection, particularly with complex lane shapes and S-curves, outperforming Rivian’s default system. However, its auto-steering capabilities are its weakest link due to the uniform torque signal it sends to the Rivian, regardless of tire wear. This can lead to difficulties in navigating certain corners, requiring driver intervention.

Hands-Free Driving and Customization
Despite its limitations, the Comma 3X enables hands-free driving on various roads, not just pre-mapped highways. It’s also highly customizable, allowing drivers to adjust parameters like driving personality and cornering aggression. The system can be integrated with OpenPilot software for additional features like adaptive cruise control and automated lane changes.
Installation and Hardware
Installing the Comma 3X requires removing trim, routing cables, and mounting an adhesive device to the windshield. While the process can be challenging, it’s a one-time task. The device boasts a Qualcomm Snapdragon 845 processor, 6-inch OLED display, and advanced camera system.
Future Developments
The Comma 3X community is working on ‘Longitudinal’ capabilities, which would enable speed control and potentially stop sign/stop light recognition. However, this requires additional hardware and is still in development.
Conclusion
The Comma 3X offers a promising but imperfect hands-free driving experience for Rivian R1T owners. While it provides enhanced features and customization, it demands more driver attention than expected, particularly in certain driving scenarios. For enthusiasts willing to invest time and money, it represents a step towards more advanced autonomous driving capabilities.

As the automotive industry continues to evolve, devices like the Comma 3X are pushing the boundaries of what’s possible with aftermarket technology. For $2,000, Rivian R1T owners can experience a more advanced level of autonomy, albeit with some limitations.