on this bosch d/w, 1 means a heating fault. since you have replaced the control board we can rule that out. there is a secondary board at the bottom of the right hand side. check for broken solder joints. bosch heaters are hard to access and the tub would have to be removed to check or replace. heater should read 11 ohms if you gain access. other problems could be the safety thermostat or the ntc. again, hard to get to.