MAKCU Troubleshooting
LED status guide and troubleshooting steps for MAKCU device issues.
LED Status Guide
MAKCU uses LEDs on both sides to indicate system status and help you troubleshoot issues. The LEDs can be solid (on or off) or blinking.
Left Side (Device Side)
The left side LED shows the status of the USB device connection to your computer.
Solid ON (Green)
Meaning: USB device is connected and working correctly
Action: No action needed - everything is working
Solid OFF
Meaning: No USB device connected
Action: Check USB cable connection and ensure device is powered on
Slow Blink (500ms on, 500ms off)
Meaning: Warning - system is adjusting settings
When it occurs: Baud rate is being changed or system is reconfiguring
Action: Wait a few seconds - this should resolve automatically. If it persists, try restarting MAKCU.
Right Side (Host Side)
The right side LED shows the status of the USB host connection to your mouse/keyboard.
Solid ON (Green)
Meaning: USB host is connected and working correctly
Action: No action needed - everything is working
Solid OFF
Meaning: No USB device connected to host
Action: Connect a supported mouse or keyboard to the right side USB port
Slow Blink (500ms on, 500ms off)
Meaning: Warning - temporary issue detected
When it occurs: USB request is busy (normal during operation) or system is handling a temporary condition
Action: Usually resolves automatically. If it persists, check device connection.
Troubleshooting Steps
Slow Blink Persists
Problem:
LED keeps blinking slowly and doesn't resolve
Possible Causes:
System stuck in configuration state, baud rate change didn't complete, or warning condition not clearing
What to Do:
Wait 10 seconds - some operations take time, power cycle the affected side, check for any error messages in device manager, or reflash if problem continues
LED Not Responding
Problem:
LED doesn't turn on or change state at all
Possible Causes:
LED hardware issue, firmware not running, or power issue
What to Do:
Verify device is powered (check USB connection), check if device is recognized in device manager, try reflashing the firmware, or if still not working, there may be a hardware issue
Device Not Working Despite Green LED
Problem:
LED shows solid ON (green) but mouse/keyboard doesn't work
Possible Causes:
Device driver issue on computer, USB port problem, or device compatibility issue
What to Do:
Check device manager for any error icons, try a different USB port, verify CH343 driver is installed correctly, check if COM port number is below 10, or try a different mouse or keyboard to test
Baud Rate Mismatch / Software Not Connecting
Problem:
MAKCU is not changing baud rate or software is not connecting to MAKCU.
Symptoms:
- Software cannot communicate with MAKCU
- MAKCU not responding to commands
- Connection timeouts
- Device appears connected but no data exchange
Solution:
Open device manager and change the com port to be any number below 10 (you may force a com port number if all are in use). Ensure baud rate is matched to the software's expectations. The MAKCU.com website and the AIO tool expect MAKCU to be running at 115200 (1 flash mode). Users must ensure that baud rate 115200 is enabled to communicate with the website and tools.
- Check the baud rate indicator LED (left) when MAKCU starts - it should flash 1 time for 115200
- If baud rate is incorrect, press the left button 4 times fast to change it
- Ensure USB 1 + USB 2 are connected for MAKCU to have power to change baud rate
- Change COM port in your software settings to match MAKCU's
- Verify baud rate matches between MAKCU and your software
- If using MAKCU website or AIO tool, ensure baud rate is set to 115200
Important: USB 1 + USB 2 must be connected for MAKCU to take power. USB 2 does not provide power to MAKCU - this prevents back feeding to the main PC and 2nd PC from both USB ports.
Cannot Flash from Website - USB Disconnecting
Problem:
Cannot flash MAKCU from the website. Device Manager shows USB 1 or 3 disconnecting constantly.
Possible Causes:
MAKCU is not flashed - this is the default factory state of the ESP32-S3 chip.
What to Do:
This is normal for unflashed devices. Hold the button down correctly and insert the USB cable. The Device Manager will stop looping and you are ready to flash. After the first flash, this will not happen again.
Quick Reference
| LED State | Left Side Meaning | Right Side Meaning | Action |
|---|---|---|---|
| Solid ON | Device connected | Host connected | Working - no action needed |
| Solid OFF | No device | No device | Connect device |
| Slow Blink | Warning/Adjusting | Warning/Temporary | Wait, usually resolves |
Still Having Issues?
If you've tried all troubleshooting steps and the problem persists:
Verify Setup
Ensure both sides are correctly flashed and configured
Check Connections
Verify all USB cables and connections are secure
Driver Check
Confirm CH343 driver is installed and COM port is below 10
Supported Device
Ensure you're using a supported mouse or keyboard
Reflash
Try reflashing both sides with the latest firmware
Hardware Check
If LEDs don't respond at all, there may be a hardware issue