Kenwood dishwasher KDW12ST3A

Hi. Dishwasher heater pipe fell off = massive flood = E4 fault code. I repaired this with narrow hose clips as is usual with these and look a like machines but now all I get `–.–` on the display. Can`t set any programme despite holding programme button down for 4 secs+. Have checked pump- works when float swt is triggered via a screwdriver, door m/swt, motor, p/swt, element tube,mains t/block all check out with meter. Had a look at pcb for blown tracks as customer said trip went off when it went wrong- all seems ok visually with the pcboard. Anyone got any other ideas please?