Jackson 200B Series Commercial Dis...

We are far out in the boonies or you could say the country so we can't get anyone to service our not that old Commercial Dishwasher.  What it does is fill continuously and keeps draining.  It never goes into a cycle.  It runs and runs and runs.  We also noticed the water never gets hot probably because it never enters a cycle.  If the unit is running constantly with water coming in and draining immediately what should we look for?  Once power is supplied to the unit it will run with the continuous water problem, but if we turn the power off the unit will stop.  We're thinking maybe a timer problem or possibly a solenoid fill valve.  We just want it fixed for our small town cook.  What do the Wiz's think the problem is?