I have a 13,000 gal in ground pool with a T-3 Cell. Both the cell and motherboard are 1 year old. I am showing 3600 salt, but the pool store is reading it at 2400. I had it checked again the following weekend, still 1000+ difference. I brought the cell in to be checked, it passed. I installed a new motherboard and no change. I tried to reset using the off/auto/off method, but my instant salt reading is within 100-200 of what it's showing originally. The cell previously (month or so ago) had significant build up. I did an acid wash to clean it out. I checked again, and it looks completely clean. Everything is generating with no additional lights, and the pool looks good. I'm not sure what else could be the problem.