I have a Culligan Mark 100 softener that is suddenly having problems. It appears to be stopped in the regenerant draw position which leaks water into the drain constantly. Up until this point it has worked fine. After regeneration two days ago the display showed CS and was leaking. I unplugged it for more than four hours to let the capacitor die, so it would return to the default settings. Upon plugging it back in it went into the regeneration cycle like it's supposed to, only to stop back in the same spot after a while, with CS on the display again. To make a long story short, I replaced the seal pack and eductor sleeve assembly. I also cleaned everything I could with Iron Out. Resetting the unit makes it return to default settings and seem to go through a regeneration cycle, but it eventually ends up in the regenerant draw position with water leakage. I don't know how to test the circuit board. Is the next step calling in Culligan Service? Thanks.