I have an IC 40 unit that has just passed 3 yrs old. After cleaning the unit and filters the system worked great for about 2 weeks. Now when it turns on the bottom 4 indicator lights are green except cell which is off and the three top salt lights cycle till the finally set to the green, indicating good salt. When the salt light goes green, the bottom flow light turns red. Not sure whatt to make of it, on phone pentair is not much help since the 3 year deal has passed.

Check all the connections to be sure they're tight. You can short the flow switch pins to check the flow switch. Don't leave it that way but it's a good check.