Pool Pilot error message: "warning check/clean cell"

[isamisis]

I bought and installed an AutoPilot DIG-220 in 09/24/2006. I chose the cell size of SC-48. I had to replace the SC-48 on 10/26/2009. I monitor the cell monthly and clean if needed per instructions in the manual. I began getting the CHECK CLEAN CELL as well as LOW AMPS/CELL? immediately after the last cleaning. My salt level was low so I added 200 lb. of salt. My salt level has been verified and is at least 3000 ppm. I re-calibrated the salt level on the DIG-220. The cell is clean, I live in AZ and the water temperature is above 75 degrees. I ran a TEST POOL PILOT and the Volts = 17 and the Amps = 3.1/3.2 on Power Level 2. I bought a new cell cord in Oct 2009 when I bought a replacement SC-48. Tonight, I replaced the existing cell cord with the new one when it seemed the salt level was not at fault and the Amps/Volts remained the same (17v/3.1a). I hate to imagine my ALMOST one year old SC-48 is defective when the last cell lasted 3 years. The two outer blades on the SC-48 show no wear. My DIG-220 software version is 4.2. Is another SC-48 purchase in my future?