Error code overview
E28 on this dishwasher is a clue for diagnosis, not a spare-parts list. In a mudroom kitchen, a detergent cup was in play when the door was just latched; keep E28 with this dishwasher rating plate.
Model compatibility: La Cornue reuses codes across series and model years, so E28 may mean something different on another appliance or generation. Confirm this against your model’s documentation and record your full model number before acting.