Display is on but buttons do not respond; unit stuck in one mode.

Safety: Unplug the unit before removing the control panel.

Steps:

• Dry panel: If the panel appears foggy or wet, allow it to dry completely. You can gently warm the area with ambient air (do not use high heat).
• Inspect ribbon cable: Remove the control panel and check the ribbon cable for corrosion or damage. Reseat it firmly.
• Test buttons: With the panel removed, press each button and feel for a positive click. Mushy or stuck buttons indicate a worn keypad.
• Replace keypad/UI: Install a new user interface / keypad assembly if buttons remain unresponsive.