Unofficial documentation of unofficial fixes and tweaks to comma and unofficial openpilot hardware

The [comma.ai Discord][cdiscord] isn't really a good place to store answers or guidance to questions about repairing and maintaining the hardware. Discord's search is terrible, and the content inside of it isn't accessible to search engines. This is an attempt to document some of the common issues and fixes that were discussed in the Discord onto the public internet so that they can be found by search engines.

[!TIP] This document is very long, clocking in at 50+ pages if printed out. You are absolutely not expected to read it all with full attention in one sitting. Use 🤖 AI assistants to help you find the relevant sections faster.

We recommend DeepWiki as it is a good choice for querying with citations and references.

• DeepWiki may lag behind the latest copy of the document by a week.
• Consult the original sections of the document as DeepWiki may not be able to see or show images.

To use DeepWiki, just go to the link below and enter your question in the chat interface:

https://deepwiki.com/ophwug/docs

about openpilot hardware!

You are encouraged to share DeepWiki conversations links in Discord if you aren't sure it is interpreting this document correctly.

Of course, other 🤖 AI assistants such as ChatGPT, Claude, or Gemini can also be used once you pass them the URL of this repository: https://github.com/ophwug/docs

[!WARNING] Always verify with original sources: When using DeepWiki or any AI assistant, remember to check the original cited text and images in this document. AI assistants may not be able to properly interpret images or diagrams, and their understanding of visual content may be incomplete or inaccurate. They may also have biases that are incorrect within the openpilot community. Always cross-reference important information with the original source material. This is a warning that applies to all AI assistants, not just DeepWiki and not specific to this document.

This document may also include links to other non-comma.ai Discords as well.

The format of this document is organized by cases. Please feel free to add your own cases, pull requests, and solutions.

This is not an official document and is not endorsed by comma.ai. However, it is supported by users and readers like you so please do feel free to make suggestions and submit pull requests!

Also, please do report back if the remedies work or don't work. Discord, GitHub issues, etc. This is a living document!

Be aware Amazon links are Amazon Affiliate links. If you buy something through them, I may get a small commission at no extra cost to you. This helps support purchasing some of the supplies, services, and tools to document these cases.

Table of Contents

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• Discords and Discussions of Note
• General Notes
• Preventative and Recommended Measures
• Hardware Documentation
  • Official Hardware Documentation
  • Reverse Engineered Community Clones and Alternative Hardware Documentation
  • Taxonomy
    • Panda
    • comma.ai Harness
• Common to all comma devices
  • The Bad OBD-C Cable Case
  • The Bad OBD-C Port Case
  • The Bad Car Harness Case
  • The Bad IR Blaster Case
  • The Running Too Old Of An OS Case
• Common to all comma two family devices
  • The Can't Proceed To Installation Because Wi-Fi Can't Connect To Internet Case On My comma two
• Common to all comma three family devices
  • The Build Error On Boot Case
  • The OS is Messed Up Case
  • The Blown Fuse Case
  • The Bad Supercapacitor Case
  • The Screen Doesn't Work or is Dying Case
  • The Fan Death Case
  • The Uncleaned Fan Flux Case
  • The Poor GPS Signal Case
  • The Bad or Dead SOM Case
  • The Damaged Ribbon Cable Case
  • The SIM Card Is Stuck Case
  • The Stuck On Registration Case
  • The Bad Screen Connector EMI Filters Case
• comma three (C3)
  • The Swampy No Panda Case
  • The Screen Colors Are Really Off Case
  • The Burned MOSFET Case
  • The Camera Malfunction Case (C3)
  • The NVMe drive not mounted Case
• comma threex (C3X)
  • The No Panda on C3X Case (Software)
  • The No Panda on C3X Case (Hardware)
  • The Fried Panda Case (C3X)
  • The Wide Camera Malfunction Case (C3X)
  • The Bad Step Down DC/DC Regulator Case
• comma four (C4)
  • The Cable Not Plugged In All The Way Case (C4)
• See Also

<!-- END doctoc generated TOC please keep comment here to allow auto update -->

Discords and Discussions of Note

There will be links to Discord conversations.

You must join the server with an invite linked for links to channels to work.

• comma.ai Discord (If unmarked and a link to Discord, it will be this)
  • #hw-three-3x
• openpilot enthusiasts Discord (OPC), a degenerate community offshoot Discord

This document is generally discussed here and there in #hw-three-3x. However, you're welcome to just make issues and discuss in the GitHub issues of this repository too.

General Notes

[!CAUTION] OBD-C outputs 12V without negotiation, NOT 5V! The harness box outputs 12V over the OBD-C port immediately and is NOT a valid or compliant USB-PD port. It does not perform any power negotiation and supplies 12V directly immediately upon connection. Despite the physical similarity to USB-C connectors, DO NOT connect standard USB-C devices (phones, tablets, laptops, etc.) to the OBD-C port on the harness box. Doing so WILL damage or destroy the connected device. OBD-C is only compatible with comma devices and other devices specifically designed to accept 12V input over this port.

• Always install stock or comma openpilot first to make sure the issue is not software related as a starting point.
  • comma.ai support will not help you if you are not running stock or comma openpilot.
  • The comma Discord (outside of #custom-forks) will only support comma openpilot.
  • If you can't install stock or comma openpilot (like for vehicle support reasons), talk in #custom-forks or visit your fork's Discord and discuss the issue.
• If your device is under return or warranty period, you should contact comma.ai support first.
  • The warranty period for new comma devices is 1 year from the date of package arrival. (Source)
  • ⏱️ "for anyone worried about slipping out of warranty, you’re good if the ticket was opened before the return/warranty period." - adeeb, comma staff lead
  • If you select the option "happens while driving" (paraphrased) when submitting a support ticket, there will be a question about providing a "route" in order to proceed with the ticket. If you follow up to step 5 of this the quick usage guide for the op-replay-clipper tool (https://github.com/nelsonjchen/op-replay-clipper), you will end up with a URL. You may skip step 4 about uploading. You can provide that URL to comma support as the "route" they are requesting. Unfortunately, comma has not fixed a long standing issue about describing what a route is or how to get one, so that tool's instructions are the best available documentation for now.
    • If you don't see anything in comma connect or cannot generate a route, just select the negative about "happens while driving" and explain instead it actually does happen while driving.
• If your C3X is out of warranty, the rough cost to repair from comma [is $500 for their C3X Out Of Warranty Repair service](https://comma.ai/shop/comma-3x-out