Power off the board and disconnect the power supply
Disconnect the LCD panel and any external cables
Locate the reset button, jumper, or reset pads on the board
If a reset button is present, press and hold it while powering on, then release after a few seconds
If a reset jumper is present, move it to the reset position for a few seconds, then return it to the normal position
If reset pads are present, short the reset pads briefly with the board powered off, then power on normally
If the board has an on-screen menu, open the menu and select factory reset or default settings
Reconnect the LCD panel and cables after the reset
Power the board back on and verify the settings have returned to default
If the board does not respond, repeat the reset procedure using the correct jumper or button for the specific model