I have a Pool Pilot Cubby Digital that's been working fine for almost a year. New SC36 cell, new tri sensor and new cords. It's been working fine all summer. Noticed over the weekend error message "Cell Inspection Due Now" on the display. Saturday, I took out the cell, it's clean, no scales, cleaned the small filter, checked flow and tri sensor and put it all back together. The message comes right back as soon as I turn the unit back on. I can hit select to clear the message and it will go back to the normal display with everything working properly but then the next day when the timer comes on it comes up with the same error message. Any ideas as to either what's causing it or how to get it removed?