AquaRite Chlorine Generator issue

AquaRite Chlorine Generator keeps telling me to check salt. It reads 2500 but my test strips and the local pool supply company checks my water at 3100  I have recalibrated the defaut screen, checked power supplies and followed the AquaRite diagnostic manual to check voltages and Ohms.  I have had the T cell checked twice and have not found any issues. I actually chaged the PCB and have the same problem.  I am at a loss as to what the next step should be… Any suggestions?