Autotrol 255 Problem

I have a three-year old Autotrol 255 with a 440 timer. It was working fine until a week ago. Now, when the regeneration process runs, it sounds like it's running through the process okay, but it doesn't draw any brine AND it also doesn't send any water to the brine tank during the fast rinse/refill step. Following the manual, I've replaced the check valve (there was no ball in the original one!), I've cleaned the injector and injector screen. Is there one failed item that can cause both of these symptoms? Any advice would be appreciated... Thanks!

air leak

usually if the unit wont draw brine the first thing to
check is wether their is a leak in the suction line...

usually it will fill the brine tank too full over a ffew cycles

Make sure it is plugged into a working 120v receptacle and keeps time and rotates the flapper valve cam shaft during a manual regeneration.

Remove the injector and make sure you can see light through it length wise and that is not partially blocked.

Remove the salt dose control and make sure it is not blocked. Remove the injector and the injector screen and run a small brush through the injector/screen passage way; in the injector hole out the screen hole on the other side of the control.

Thanks!

Thanks for the suggestions on the Autotrol 255 problem. It DID turn out to be related to the suction line from the brine tank - it had a clog in the bottom of the feed line. Thanks again... - js