Flip the circuit breaker switch that corresponds to the Bosch SHX46A dishwasher to the "Off" position to disrupt the supply of electricity to the appliance.
Open the Bosch SHX46A dishwasher and locate the two T-20 Torx screws on the sides of the door. Remove the screws to free the fascia panel; set the removed screws aside.
Examine the black control unit on the back of the fascia panel and note the placement of the wiring connections to make reassembly easier. Pull gently on the wire harnesses to disconnect them from the control unit.
Bend back the metal tabs that hold the control unit to the fascia panel with a flathead screwdriver. Slide the control unit from its housing.