Craig R Yorba Linda , CA November 12, 2018 Appliance: Samsung Dishwasher DMT400RHS/XAA Samsung Dishwasher Dmt400rhs/Xaa / : Would not run, no code, nothing. How to replace Assy Display;Dmt400,Ct50. First replaced main board. Did not fix the problem. Replaced LED display board and that fixed it. 1 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: 15-30 minutes