Always verify your panel's voltage requirements before connecting power. Applying 12V to a 3.3V panel will cause permanent hardware damage.

| Symptom | Likely Cause | Solution | |---------|--------------|----------| | Display shows “SD Error” | Incompatible SD card format | Reformat to FAT32 with 4096 byte sectors. | | Motors vibrate but don’t move | Incorrect step pulse timing in V1.6 | Send $1=25 (step idle delay) and $3=2 (invert direction mask). | | V1.6 rejects G-code with “Unsupported command” | Firmware was compiled without full G-code set | Re-flash with the correct variant (GRBL 1.1f or CNCjs). | | Jittery display after update | Conflicting refresh rate with older LCD | Downgrade to V1.5 – OR – replace 59-ga ribbon cable. | | Cannot enter bootloader mode | Corrupt boot sector | Use USB-TTL to force flash using avrdude with the -F flag. |

: The menu interface remains basic and dated compared to modern Smart TV platforms. Installation Tip