How to Factory Reset or Flash Firmware for Your Keychron C3 Pro Keyboard?

Troubleshooting? Or don't know what's going on with the keyboard? You may try factory reset.

Note: If everything works fine with your keyboard. Please don’t flash the firmware. There is a chance it can damage your keyboard.

1. Plug in the power cable and factory reset the keyboard by pressing fn + J + Z (for 4 seconds).

2. Download the C3 Pro firmware and download the QMK Toolbox. (If the download link below does not work, use this link:

3. Unplug the power cable from the keyboard.

4. Open the QMK Toolbox.

5. Remove the space bar keycap to find the reset button on the left side of the space bar switch on the PCB.


6. Press down and hold the reset button.

7. Plug in the power cable. The keyboard will enter into DFU mode. Then, the QMK Toolbox will display in yellow words "***DFU device connected".


8. Click open and choose the Keychron C3 Pro firmware. Click the Flash button. It will start flashing. (Note: Do NOT unplug the power cable while it's flashing.)


9. Wait a few seconds and when you see the content below, it means the keyboard has flashed successfully factory reset.


10. Factory reset the keyboard again by pressing fn + J + Z (for 4 seconds).

If VIA can't pair with your Keychron C3 Pro after you tried flashing, you need to follow these steps:

1. Reconnect your keyboard power cable.

2. If VIA still doesn’t pair together after you reconnect the power cable, download the Keychron C3 Pro JSON file.

3. Open online VIA and turn on "Show Design tab" on "Settings" tab.
4. Click on "Design" tab, then click on "Confirm".
5. Drag the JSON file into the “Design” tab on the VIA.
6. A window will pop out after you drag the JSON file, please click on "Keychron C3 Pro" and then click on "Connect".

7. You should see the keyboard's keymap on the Configure tab now.

You may contact if a defect covered by the warranty arises in your product within the warranty period. Keychron will honor the warranty of our C Pro series keyboard (e.g.: C1 Pro, C2 Pro, etc.) by one of the following methods at our discretion:

- Defects of C Pro series keyboards have been caused by manufacturing: We will only replace the defective parts of the keyboard, not the whole keyboard, as its highly customizable and easy to be rebuilt.

- Defects of C Pro series keyboards have been caused by disassembling our product, improper installation, non-factory repairs/modifications, improper adjustment of the product, or neglect, including but not limited to “burn-in”, and similar wrongful use: We will NOT offer free service. We only offer paid service to replace the defective parts at your own cost (including the cost of parts, shipping fee and tax if applicable).