Hello,
I am just a single mom trying to troubleshoot her own pool problem. My auto pilot equiptment Check Sensor light is flashing. The display says Purifier Off, Check flow. Help.

Hi Ms Jenna, welcome!
The Pool Pilot will display the Check System light for any warning conditions. For the Purifier Off, Check Flow, it means there's not enough water flow going to the manifold assembly. This can be due to several reasons. The easiest ones to check are the following:
Skimmer and Pump Baskets.
Diverter valves to the pump.
Make sure the pump is on and moving water through it by inspecting the pump basket area, which should have a clear lid to see into the trap.
Check your filter pressure to make sure you don't need to backwash or clean your filter.
Check all valves between your pump and AutoPilot manifold to make sure there aren't any that are closed or diverting flow from the manifold.
At the manifold, make sure the tri-sensor cord is plugged into the tri-sensor.
Turn off the pump and loosen the manifold union, where it has a label that says "Clean Union Screen Regularly". There is a mesh screen to catch debris, and can get clogged.

OK, that's a start.

Thanks so much...I had checked the baskets and done a back wash, but I did the rest of the things on your list. The mesh screen did have some debris, and although the sensor cord was tight, I disconnected it and reconnected it. Now, the check flow indicator is not on. However, it says Warning, Low Amps-Cell? When I run a test, it says 28V-1.8A. Is this a problem? Ideas?

How old is the system? It's either due to low salt (take a water sample in and have it checked), scaled cell (remove the cell and inspect for white calcium buildup between the blades), failing cell (while you have the cell out, inspect the two outer blades for erosion of the edges. All the blades should be the same length on both ends, but when the cell starts to fail, the edges of the two outer blades will wear down), or a bad cell cord (remove and inspect both ends of the cord for debris or corrosion).