SHU 33 MODELS
To start test program, press and hold both POWER SCRUB PLUS and RINSE & HOLD program buttons, then turn unit on by pressing ON/OFF button. When program buttons are released, lights above them will flash. To end test program, press ON/OFF button.
To check program indicator lights (POWER SCRUB PLUS, REGULAR WASH and RINSE & HOLD), press and hold each program button. When REGULAR WASH program button is pressed, CLEAN light also comes on.
To start testing, press both POWER SCRUB PLUS and RINSE & HOLD buttons a second time. When testing has ended and a fault was detected, the following indicator lights will be lit:
POWER SCRUB PLUS = Heater fault
REGULAR WASH = Water filling fault (over or under filling)
RINSE & HOLD = NTC (temperature sensor) fault – note circulation motor stops shortly after it started during an NTC fault
To check for heater, high limit or flow switch problems, start testing until heating starts. Using a meter with a current coil, measure current going into dishwasher. If current is ~ 11 A, then heater, high limit and flow switch are OK. If current stays at ~ 1.5-2 A, then heater, high limit or flow switch are faulty.
If water level switch (f1) has failed (opened), REGULAR WASH light will come on and unit will continually fill and drain where testing won't be completed. If flow switch (e5) has failed (opened), water won't heat (to 150ºF) and water won’t stop circulating. If NTC probe (f2/f4) has failed (opened), RINSE & HOLD light will come on immediately and testing will end shortly after water has started circulating.
If more than one fault occurs, more than one light will be lit.
Sounds more like the light will come on and stay on when a problem has occured....esp for a washability problem I'd check other things first before going into the test program.