Keychron K4 RGB Hot Swappable Mechanical Keyboard User Manual

Introduction

This manual provides comprehensive instructions for the setup, operation, and maintenance of your Keychron K4 RGB Hot Swappable Mechanical Keyboard. Designed for productivity and a tactile typing experience, the K4 features a 96% layout with 100 keys, offering both Bluetooth wireless and USB wired connectivity. It is compatible with both Mac and Windows operating systems.

Package Contents

• Keychron K4 Mechanical Keyboard
• USB Type-C Cable
• Keycap Puller
• Switch Puller
• Extra Keycaps for Windows and Mac operating systems
• User Manual (this document)

Setup

1. Initial Charging

Before first use, connect the keyboard to a USB power source using the provided USB Type-C cable. The keyboard features a 4000 mAh battery, providing up to 240 hours of usage with the backlight disabled.

2. Connectivity Modes

The Keychron K4 supports both Bluetooth wireless and USB wired connections.

Image: The Keychron K4 keyboard is designed for broad compatibility, supporting both Mac and Windows operating systems, and connecting seamlessly with various devices including desktops, laptops, and smartphones/tablets.

2.1. Bluetooth Connection

1. Ensure the keyboard's mode switch (located on the side) is set to "BT" (Bluetooth).
2. Press and hold the Fn + 1 (or Fn + 2 or Fn + 3) key combination for 4 seconds until the '1' (or '2' or '3') key flashes rapidly. This indicates the keyboard is in pairing mode.
3. On your device (computer, smartphone, tablet), enable Bluetooth and search for "Keychron K4".
4. Select "Keychron K4" from the list of available devices to complete the pairing process. The corresponding number key will stop flashing and remain solid when connected.
5. The keyboard can connect with up to 3 devices and switch between them easily using Fn + 1, Fn + 2, or Fn + 3.

2.2. USB Wired Connection

1. Ensure the keyboard's mode switch is set to "Cable".
2. Connect the USB Type-C cable from the keyboard to your computer's USB port.
3. The keyboard will be automatically recognized and ready for use.

3. Operating System Switch

The Keychron K4 has a dedicated switch for Mac and Windows layouts. Locate the OS switch on the side of the keyboard and set it to your desired operating system for optimal key mapping.

Image: The Keychron K4 keyboard seamlessly integrates with Apple devices, as shown here next to an iMac and Magic Mouse, highlighting its Mac compatibility.

Operating Instructions

1. Key Functions and Layout

The K4 features a 96% layout with 100 keys, including a number pad. It provides all necessary Mac function keys and is fully compatible with Windows. Extra keycaps for both operating systems are included for customization.

Image: A comprehensive view of the Keychron K4 keyboard, highlighting its compact 96% layout which includes a full numeric keypad, and its vibrant RGB backlighting.

2. Backlight Control

The K4 features enchanting RGB backlighting with over 15 types of flashing light modes. All backlight controls are managed directly from the keyboard without the need for software.

• Fn + Light Bulb Key (F5): Cycle through different RGB lighting effects.
• Fn + Left Arrow: Decrease backlight brightness.
• Fn + Right Arrow: Increase backlight brightness.
• Fn + Up Arrow: Increase backlight speed/effect.
• Fn + Down Arrow: Decrease backlight speed/effect.

Image: A detailed shot of the Keychron K4's RGB backlighting, showcasing the vibrant and customizable illumination beneath the keycaps.

3. N-Key Rollover (NKRO)

The K4 supports N-key rollover (NKRO) in wired mode, allowing all keys to be registered simultaneously. In wireless mode, it supports 6-key rollover (6KRO).

Maintenance

1. Cleaning the Keyboard

To clean your keyboard, first disconnect it from all power sources. Use a soft, lint-free cloth slightly dampened with water or a mild cleaning solution. Avoid spraying liquids directly onto the keyboard. For cleaning between keycaps, use compressed air or a small brush.

2. Hot-Swappable Switches

The K4 hot-swappable version allows you to personalize your typing experience by changing switches without soldering. This feature enables easy replacement of switches if they become faulty or if you wish to try different switch types (e.g., Gateron G Pro Brown, Red, Blue).

Image: This image demonstrates the hot-swappable capability of the Keychron K4, showing various Gateron switches detached from the keyboard's PCB, allowing for easy customization or replacement.

2.1. Replacing Switches

1. Use the provided keycap puller to gently remove the desired keycap.
2. Use the provided switch puller to carefully grip the switch from its top and bottom clips. Pull straight up to remove the switch from the PCB.
3. Align the pins of the new switch with the holes on the PCB. Ensure the pins are straight.
4. Gently push the new switch into place until it clicks securely. Do not force it.
5. Replace the keycap.

3. Keycap Replacement

Keycaps can be removed and replaced using the keycap puller. This is useful for cleaning or for installing custom keycap sets. Ensure proper alignment when replacing keycaps.

Troubleshooting

• Keyboard not connecting via Bluetooth:
  • Ensure the keyboard's mode switch is set to "BT".
  • Verify the keyboard is in pairing mode (Fn + 1/2/3 key flashing).
  • Check your device's Bluetooth settings and ensure Bluetooth is enabled.
  • Try forgetting the device on your computer/phone and re-pairing.
  • Ensure the keyboard is sufficiently charged.
• Bluetooth connection lag or disconnection:
  • Move the keyboard closer to your device to reduce interference.
  • Ensure no other strong wireless signals are interfering.
  • Check battery level; low battery can affect wireless performance.
  • Consider using the wired USB connection for critical tasks or gaming if wireless performance is inconsistent.
• Backlight not working or stuck:
  • Ensure the backlight is not turned off (Fn + Light Bulb key).
  • Adjust brightness using Fn + Left/Right Arrow keys.
  • A full charge might resolve minor power-related issues.
• Keys not responding:
  • If using wireless, check battery and connection.
  • If using wired, ensure the USB cable is securely connected.
  • For specific keys, consider the hot-swappable feature: remove the keycap and switch, inspect the switch pins for bending, straighten if necessary, and reinsert. If the switch is faulty, replace it.
• Keyboard not recognized by computer:
  • Try a different USB port or cable.
  • Ensure the OS switch on the keyboard matches your computer's operating system.
  • Restart your computer.

Specifications

Warranty and Support

Keychron products are designed for durability and performance. For specific warranty terms and conditions, please refer to the warranty information provided with your purchase or visit the official Keychron website. For technical support, troubleshooting assistance, or inquiries regarding your Keychron K4 keyboard, please contact Keychron customer service directly.

Official Keychron Website: www.keychron.com