<<<We have a *LDS5811WW
* dishwasher that suddenly will not power on.>>>
Remove the lower kickplate at the front/bottom of the dishwasher.
On the right side---there's a small TERMINAL BOX---remove the screw/box and verify 120 volts at the *black* and *white* wires. If either of these wires appear burnt/overheated (loose connections) disconnect power at the home fusebox/circuit breaker---and repair as needed.
Remove the front cover of the dishwasher (metal panel & plastic control panel).
Remove the large *white* plug from the MAIN BOARD---using the test meter---verify 120 volts at the *white* plug (not the MAIN BOARD itself).
If no voltage is detected at the *white* plug---replace both the NOISE SUPPRESSION FILTER and the MAIN BOARD.
NOTE: The NOISE FILTER is located at the bottom/right side of the dishwasher (small circuit board).
If there is voltage at the *white* plug---replace the MAIN BOARD only.