Thinking About Purchasing a Comma 3X for Your Gen1 Rivian? Start Here First.

If you’re a Rivian R1T or R1S owner thinking about installing a Comma 3X to unlock Openpilot’s advanced driver-assist features, you’re not alone—and you’re in the right place.

Before diving into harnesses, mounts, or model settings, there’s one resource you need to check out: the Rivian Comma 3X Tips & Tricks document. Created by Discord user @mcgaverty and maintained by experienced Rivian owners in the Openpilot community, this guide is the unofficial go-to reference for everything you wish you knew before installing Openpilot.

Why This Document Matters

The Tips & Tricks guide isn’t just a list of settings—it’s a collection of hard-earned knowledge from real-world Rivian drivers who’ve already gone through the process. Whether you’re trying to decide if it’s worth it, prepping for your first install, or fine-tuning your setup, this doc answers questions you won’t find in a sales pitch.

You’ll learn about:

• Power options (and why Rivians can be tricky to wire cleanly)
• Mounting solutions for a clean, stable setup
• Harness recommendations (including the differences between the Comma and Lukas Loetkolben harnesses)
• Feature tradeoffs, like turn signal control and auto high beams
• Compatibility notes for different model years, trims, and factory tires
• How to avoid common pitfalls and get the most out of your Comma 3X from Day 1

Straight Talk from Rivian Owners

One of the best things about the guide is how transparent it is. The document doesn’t sugarcoat anything—it’s honest about limitations, quirks, and what still needs work. For example, you’ll find details on the difficulties involved in installation, what kind of boot times to expect, and how upcoming updates might change things.

It’s not just a tech doc—it’s a living guide, built by the community for the community.

Ready to Dive In?

Check out the full Rivian Comma 3X Tips & Tricks guide here:
https://docs.google.com/document/d/1clodGRssTx-dSPSUrQITq_vqumgWcpSUw83zdcAZR-A/edit#heading=h.oyzac3b675fu

If you’re on the fence about buying a Comma 3X, or already have one and want the best experience possible in your Rivian, this is the doc to bookmark, read, and revisit often.