The SHP78DM5N comes from the D run of Bosch’s 800 Series pocket-handle dishwashers. Its rating is 42 dBA, it carries 16 place settings, and it dries with CrystalDry. Bosch moves these platforms forward by letter rather than redesign, so C and D builds have most of their hardware in common; the stainless door is anti-fingerprint.
Where they part ways is the electronics: the main board and the software on it. That matters at the parts counter: a board from the wrong generation will plug in and still behave oddly. We read the serial plate to identify the build rather than relying on the family name.
Two other repair calls turn up on this model. Cutlery that falls through the third rack and hits the arm below is one, and a slow drain caused by a partly blocked air gap in the sink is the other.
Boards that look identical can carry different firmware by generation. The plate tells us which build you own, so the part we order will actually behave properly.
Check the air gap on the sink. A partial blockage there slows the outflow. If that is clear, the drain pump or hose is the next place we test.
One strike seldom does damage. Remove the fork and turn the arm by hand. If it spins freely, you are fine, but repeated strikes can bend it.
Book in about a minute, or call the desk. Same-day windows inside the Loop on most days, next-day across the rest of Houston.