Bosch wvt 1260 not working?

Hi I have a Bosch 1260 washer/dryer - heater wasnt working on either wash or dry -. Control board burnt had it repaired by QER but the couldnt test - anyway put it all back together - powered up and tried programme settings but all I get is blank screen - start button doesnt operate on any programme - heard about reset buttons but cant find one aywhere top, bottom, back, front or underneath. Can anybody help please