Step 1 of 7

Remove the rearview mirror cover trim

Removal method varies by car. The durable plastic often requires a strong tug to pop it off on Hondas. Toyotas often need a slide outward. If you’d like to see how it’s done, find a comma installation guide for your specific make on YouTube.

Step 2 of 7

Connect car harness into the camera

unplug existing LKAS camera connector and plug it into the harness

connector harness into LKAS camera connector and adhere harness box to the car

Unplug the existing LKAS camera connector and plug it into the harness.
Connect the other end of the harness back into the LKAS camera.
Secure harness – Find where to place the harness box so the trim can still be installed over it. Peel off adhesive sticker and attach the harness in place.

Step 3 of 7

Plug the RJ45 cable into the harness box

route rj45 cable across your car to your OBD-II port

Plug the RJ45 cable into the harness box – ensure the cable is fully seated.
The RJ45 cable must be brought across your car to your OBD-II port which is almost always found below the steering wheel to the left. Carefully run the cable behind the vehicle trim along the windshield, doorframe, or dash.
Plug the RJ45 cable into the comma power and then plug the comma power into the OBD-II port.

Step 4 of 7

Place mount high and centered on the windshield

approximate position on windshield to mount the comma device

preparation and instructions to adhere the mount to the windshield

emphasis to let mount adhesive cure for 48 hours before attaching the comma device

Mounting prep – Clean the mounting area with the included alcohol wipe and let it dry.
Positioning – Ensure the top of the mount is fully visible from the driver's seat.
Adhere mount – Peel off the 3M tape's cover on the mount. Press firmly in the center of the mount, then the edges. Ensure no bubbles form.
Let the mount cure – The mount must cure for 48 hours before installing the comma device. Skipping this step will compromise the integrity of the mount.

The mount may be difficult to slide onto the device before it's installed on the windshield. This is expected and will be easier to do once the mount is installed and fully cured.
Some force may be necessary to initially slide the device on the mount. Before applying any force, ensure the device's mount is parallel to the mount on the windshield.

Step 5 of 7

Plug in OBD-C and mount the device

plug in right-angle OBD-C cable into the harness box

clean all three lenses with the included microfiber cloth

plug in OBD-C to back of the comma device and mount the device

Plug the right-angle OBD-C cable into the harness box – Ensure the cable is fully seated. For comma 3X, ensure the straight end is connected to the harness box.
Clean all three lenses with the included microfiber cloth.
Plug in OBD-C and mount the device – Plug the OBD-C cable into the back of the comma device. Make sure the cable is all the way in.

Step 6 of 7

Pair your device with comma connect

Pair your device and claim 1 free month of comma prime with connect.comma.ai on your phone.

comma Connect

Step 7 of 7

Reinstall the rearview mirror cover trim

Ensure the car harness fully fits inside the trim. Have the OBD-C cable come out of the top.

Frequently asked questions

How and where do I buy a comma device?

The comma shop is the only official retailer of comma devices (the comma two, comma three, and comma 3X). The comma shop accepts all major credit cards. We offer free shipping in the US and $30 flat rate international shipping.

Buy the comma 3X here.

Do I need a comma prime monthly subscription to use the device?

No. comma prime is completely optional and is not needed for any core functionality. comma prime can be activated, cancelled, and re-activated at any time.

I ordered a comma device! Now what?

Congratulations! Get started by watching the Installation Guide on our setup page. We find on average the installation process takes 15-30 minutes.

If you encounter an issue, we recommend you join our Discord where hundreds of active users are available to help troubleshoot.

You can cancel your order for a full refund up until it ships through your order page.

Does installing a comma device require permanent modifications to the car?

Installing a comma device does not require any permanent modifications to your car. With the car harness, most car trims remain in place.

How do I mount my comma device?

We recommend the mount be centered on the windshield below the trim (see pictures in the Installation Guide). Be sure to leave enough room to remove the trim in the future. First, clean the windshield with the included alcohol wipe. Ensure the top of the mount is fully visible from the driver’s seat. Adhere mount: peel off the 3M tape’s cover on the mount. Press firmly in the center of the mount, then the edges to ensure no bubbles form.

Let the mount cure: the mount must cure for 48 hours before installing the comma device. Skipping this step will compromise the integrity of the mount.

The 3X mount may be difficult to slide onto the device before it’s installed on the windshield. This is expected and will be easier to do once the mount is installed and fully cured. Some force may be necessary to initially slide the device on the mount. Before applying any force, ensure the device mount is parallel to the mount on the windshield so it will slide in correctly.

IT IS THE USER’S RESPONSIBILITY TO MOUNT THE DEVICE IN COMPLIANCE WITH ALL APPLICABLE LAWS AND ORDINANCES.

Will installing a comma device void my warranty?

From the FTC website: "Simply using an aftermarket or recycled part does not void your warranty. The Magnuson-Moss Warranty Act makes it illegal for companies to void your warranty or deny coverage under the warranty simply because you used an aftermarket or recycled part."

https://www.consumer.ftc.gov/articles/0138-auto-warranties-routine-maintenance

Will my insurance cover my car with a comma device installed?

Contact your insurance provider directly; insurance coverage is between the user and their insurance provider. comma hardware users have been able to get coverage and discuss this on Reddit here.

Insurance companies are beginning to understand the safety benefits of ADAS and LKAS systems like openpilot and we have not heard of any providers rejecting coverage to comma hardware users.

I am upgrading from a comma two to a comma 3X do I need to order another harness?

No, existing comma harnesses work with these devices.

Join the conversation

Have a question or want to learn more? There are thousands of knowledgeable community members on the Discord.

Join our Discord

Developer Resources

Check out the code behind the the comma 3X and openpilot. Review, fork, and contribute to the open source ecosystem.

Visit our GitHub