Display shows E08 and unit will not accept programming changes; buttons appear unresponsive or intermittent.

Safety first: Unplug the softener before removing the front cover.

• Dry the panel: If the unit is installed in a damp area, inspect for condensation or water on the display and keypad. Gently dry with a soft cloth and allow the panel to air dry for several hours.
• Check ribbon cable: Remove the front bezel and verify the keypad ribbon cable is fully seated on both the keypad and main PCB. Reseat it if loose.
• Test buttons: With power restored, press each button and observe the display response. If some or all buttons remain unresponsive, the membrane keypad is likely failed.
• Replace UI module: Install a new Crystal Quest keypad/display module or front panel assembly as specified for your model. Reprogram all settings after replacement.