Aqua Plus Salt Pool



While getting my pool ready for the season, my display read Chlorinatior Off, Very Low Salt. I added sufficient salt to 3400 ppm, tested manually. However, display continues to read Very Low Salt. The Flow Switch will say Flow when initially starting filter but changed to No Flow after running for a while. Instant Salt reads 0000 ppm. Does my T-cell need replacing?  What about my Flow Switch?  The pool and equipment are three years old.