Polaris AutoClear still blinks low salt but the display is blank where I believe it should be showing the salt level. When I hit the test button, I get a code 91 (low salt). Salt level is definitely at 3400 as confirmed several times by Taylor salinity test and pool store test. Cell looks great, but I cleaned it anyway just to be sure. I can't be sure of the age of the control unit or the cell, but it all looks in fairly good shape. There are tamper-resistant screws on back of control unit with an odd triangle shaped head, not sure if I can get inside or do any good either way. Any ideas?
30K gallon, in-ground vinyl, swg