Salt Reading is Not Correct

I have an Aqua Plus controller that is giving me false low readings.  The local pool shop and my salt test kit (strip) both show a salt level of 4,000ppm.  The Aqua Plus reads 2,000ppm.  As a result i get "Instant Salt Chlorinator Off and “Chlorinator Off Test Salt Level” and “Check System Very Low Salt” readings.  I’ve replaced the flow switch and cleaned the T-15 salt generator with acid as per directions.  The T-15 was new as of August 2017 so less than 3 years old.  Is there a way to recalibrate the system and introduce the actual salt level, similar to putting in an independent pH measurement?  If not, what is the next step?  The system was new in 2014.  Is there a way to check the control board?

My experience is the generators only last on average about 3 years. Been in our home now for 10 years and on our 3rd T-15.