Buttons on the J+ Booster (e.g., current selection) do not respond or respond only intermittently.

Safety: Interface issues are low risk but avoid using sharp tools on the keypad.

• Clean surface: Wipe the button area with a dry, lint-free cloth to remove dirt or residue.
• Test with power-cycle: Disconnect from mains for a few minutes, reconnect, and test buttons again.
• Use alternative control (if available): If the charger can be configured via app or DIP switches, use those as a temporary workaround.
• Persistent non-response: The keypad or display PCB likely needs replacement.