Safety first: Turn off power at the breaker before unplugging the topside.

Inspect panel: Look for condensation under the display window or cracks in the overlay.
Check cable: Ensure the topside cable is not pinched and is firmly connected at the control pack.
Dry minor moisture: If slight condensation is present, allow the panel to dry with the cover open and power off for several hours, then retest.
Replace topside: If buttons remain unresponsive, replace the topside control panel with a Coast Spas-compatible model.

Topside control buttons are unresponsive or only some buttons work.

Possible Causes