Customer Questions and Answers for Dishwasher Control Board by Bosch

Hello Jeff, Before you start, kill the power supply to the unit and verify no voltage is present to the machine. Start at the power connection on the machine. Remove the kick panel and the cover where the wire nuts are located. Check to make sure the wire nuts are tight and both wires are securely in the nuts. If this checks out good, the next check is at the door switches inside the door panel. Check these for continuity and don't forget they show open unless you mash the button on the switch. Mashing the little button should give you continuity. If not, replace the door switch. Now go to the power button and make sure it shows continuity when activated. Check the float switch in the same manner also. If all of these test satisfactorily, momentarily power up the unit and test at the board for 120Vac. Remember that the door switches and the power switch have to be activated. This is best done by simply closing the door and mashing the on switch. Now you should have voltage to the board. If you have voltage to the board and the unit will not start, check for voltage leaving the board. If there is only voltage on one terminal, this is an indication of a bad board since if the board sends power out to any components, you will read this voltage on another terminal. If voltage is on one terminal, the board will require replacement.