Keychron K4 Pro Bluetooth Mechanical Keyboard

In the Box

• Keychron K4 Pro Bluetooth Mechanical Keyboard x 1
• Type-C Cable x 1
• Manual x 1
• Quick Start Guide x 1
• Extra Keycaps Set x 1

Quick Start Guide

If you are a Windows user, please find the appropriate keycaps in the box, then follow the instructions below to find and replace the following keycaps.

Mac / Windows Layout Description: The keyboard features a standard QWERTY layout with function keys (F1-F12), navigation keys (Home, End, PgUp, PgDn), a dedicated numpad, and modifier keys (Ctrl, Option/Alt, Command/Win, Fn). Specific keycaps for Mac and Windows systems are provided for customization.

Connectivity

1. Connect Bluetooth

Description: To connect via Bluetooth, switch the toggle to the Bluetooth option. Press and hold the Fn + 1 key combination for 4 seconds to initiate pairing. Search for "Keychron K4 Pro" on your device and connect. The Bluetooth indicator will flash slowly during pairing and turn off upon successful connection. This keyboard supports pairing up to 3 devices simultaneously using Fn+1, Fn+2, and Fn+3.

2. Connect Cable

Description: To connect via cable, switch the toggle to the Cable option. Connect the keyboard to your PC using the provided Type-C cable. Backlighting will be turned on automatically. Under Wired Mode, the keyboard will not enter Battery Saver Mode.

VIA Key Remapping Software

Please visit canlusevla.com to download the latest VIA software to remap the keys. VIA software only works when the keyboard is connected by wire to the computer.

The Layers

The keyboard has four layers of key settings:

• Layer 0: Activated when the system toggle is switched to Mac.
• Layer 1: Activated when the system toggle is switched to Mac and the Fn/MO(1) key is pressed.
• Layer 2: Activated when the system toggle is switched to Windows. This is the primary layer for Windows users.
• Layer 3: Activated when the system toggle is switched to Windows and the Fn/MO(3) key is pressed.

Note: When using Windows mode, it is recommended to make changes on Layer 2, not Layer 0, to avoid common user errors.

Backlight Control

5. The Backlight

• Press Fn + Q to cycle through different lighting effects.
• Press Fn + Tab to turn the backlight on/off.

6. Adjust The Backlight Brightness

• Press Fn + W to increase the backlight brightness.
• Press Fn + S to decrease the backlight brightness.

7. Adjust The Backlight Speed

• Press Fn + T to increase the light effect speed.
• Press Fn + G to decrease the light effect speed.

Warranty

The Keychron K4 Pro is highly customizable and easy to rebuild. If any keyboard components malfunction during the warranty period, Keychron will replace the defective parts, not the entire keyboard.

Watch The Building Tutorial On Our Website

If you are building the keyboard for the first time, it is highly recommended to watch the building tutorial video on the Keychron website first before proceeding with assembly.

Factory Reset & Troubleshooting

10. Factory Reset

Troubleshooting: If you encounter issues with your keyboard, consider a factory reset.

1. Plug in the power cable and switch the keyboard to Cable mode.
2. Factory reset the keyboard by pressing Fn + J + Z for 4 seconds.
3. Download the correct firmware and QMK Toolbox from the Keychron website.
4. Switch the keyboard to OFF mode and remove the space bar keycap to locate the reset button on the PCB.
5. Hold the reset key, then switch the keyboard to Cable mode.
6. Release the reset key; the keyboard will now enter DFU mode.
7. Flash the firmware using the QMK Toolbox.
8. Factory reset the keyboard again by pressing Fn + J + Z for 4 seconds.

* A step-by-step guide can be found on the Keychron website.

General Troubleshooting Tips:

• Unable to pair keyboard to device: Confirm the device is Bluetooth-capable. Restart both the device and the keyboard, then try pairing again. On Windows, new Bluetooth connections may require additional software updates; wait at least 20 minutes after pairing before restarting. Ensure the device accepts Bluetooth connections and supports an external keyboard (HID profile).
• Keyboard isn't working: For computer/smartphone: Go to Bluetooth settings, select the keyboard, and remove/delete/unpair it. Restart your device. For the keyboard: Turn the keyboard off and back on, then reconnect it to your device.
• Bluetooth connection interrupted within 10 meters: Check if the keyboard is resting on a metal surface, which can interfere with the Bluetooth signal.
• Third-party input tools: Functions of certain multimedia or function keys may be disabled due to compatibility issues with Windows/Android OS versions, brands, or drivers. Ensure your operating system and drivers are up to date.
• Certain multimedia keys or function keys do not work: This can be due to compatibility issues. The document lists specific multimedia and function keys that may be affected.

K4 PRO BLUETOOTH MECHANICAL KEYBOARD SPECIFICATIONS

Technical specifications are subject to change without notice.

K4 PRO BLUETOOTH MECHANICAL KEYBOARD OVERVIEW

Overview: The keyboard features distinct layouts for Mac and Windows operating systems. Key components include:

• 1. Bluetooth indicator: Shows Bluetooth connection status.
• 2. BT OFF Cable: Likely refers to the USB Type-C port for wired connection and charging.
• 3. Mode Toggle Switch (Win/Android Mac/iOS): Switches between operating system modes.
• 4. Charging port: USB Type-C port for charging.

Key Description

LED Status Overview

Function Description: Charging

Plug the provided USB Type-C cable into a USB port and the keyboard. The Charging Indicator shows the battery status: blinking red for low battery (below 15%), static red while charging, and static green when fully charged (approximately 3 hours). The Keychron K4 Pro is compatible with all USB ports. For optimal performance, use a 5V 2A adapter or USB 3.0. The keyboard can be charged in Bluetooth or wired mode. Keychron is not responsible for issues caused by improper charging.

Bluetooth / Wired Mode (Mode Toggle Switch)

Wired Mode

1. Switch the toggle switch to the Cable option (requires USB cable plugged in).
2. Connect the provided cable to your PC and keyboard.
3. Backlighting will be turned on.

*Under Wired Mode, the keyboard will not enter Battery Saver Mode.

Bluetooth Mode

1. Switch the toggle switch to the Bluetooth option.
2. Backlighting will be turned on.
3. Hold Fn + 1 for 4 seconds to activate Bluetooth pairing. The Bluetooth indicator flashes for 3 minutes to detect pairing.
4. Search for "Keychron K4 Pro" on your device and connect. The indicator goes off after successful pairing.

Note: This keyboard supports pairing up to 3 devices simultaneously via key combinations Fn + "1", Fn + "2", or Fn + "3".

*The Bluetooth indicator will continue to flash for 3 minutes.

**Slow or failed connections may occur due to different Bluetooth versions; ensure all settings are correct.

Switch Bluetooth Devices

Short press key combinations Fn + "1", Fn + "2", or Fn + "3" to switch to other paired devices.

Reconnect

1. Switch the keyboard to the Bluetooth option to activate it.
2. The Bluetooth indicator flashes for 4 seconds and automatically pairs with the last paired device.
3. If the Bluetooth indicator is off, press any button to re-establish the connection.

*The keyboard must have been previously paired with the device to perform this function.

Turn Off The Keyboard

Switch the keyboard to the OFF option.

Backlight Setting

• Short press [light-icon] to switch between different types of lighting effects.
• When backlighting is on, press [brightness-icon] button to switch among them.

OS Toggle Switch

1. MAC/IOS: Switch the toggle to Mac/iOS when connected to a Mac or iOS operating system.
2. WINDOWS/ANDROID: Switch the toggle to Windows/Android when connected to a Windows or Android operating system.

*When using the Windows/Android mode, the [windows-key] and [alt-key] keys are used for "Windows" and "Alt" functions respectively.

Input Method Switch

For iOS:

Input method switch: Ctrl + Space

Caps Lock: Navigate to Settings > General > Keyboards > Hardware Keyboard > Caps Lock Language Switch.

For Android:

Input method switch: Shift + Space

NOTE: Functions of certain multimedia keys may be disabled due to compatibility, versions, brands, and drivers of Windows/Android OS. Frequent OS switching may impact keyboard operations.

Safety Precaution

• Keep the product, accessories, and packaging parts out of the reach of children to prevent accidents and choking hazards.
• Always keep the product dry to avoid corrosion.
• Do not expose the product to extreme temperatures below -10°C (5°F) or above 50°C (131°F) to preserve the lifespan of the keyboard.

FCC Compliance

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. Changes or modifications to this unit not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment.

NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.

This device and its antenna(s) must not be co-located or operation in conjunction with any other antenna or transmitter.

Radiation Exposure Statement: The device has been evaluated to meet general RF exposure requirement in portable exposure condition without restriction.

Contact Information

Keychron, Inc.
Dover, DE 19901, United States

Find us at:

• Website: https://www.keychron.com
• Support Email: Support@keychron.com
• Social Media: @keychron (Instagram, Facebook), @keychronMK (Twitter)

Designed by Keychron
Made in China