how can i fix my dishwasher, whirlpool, du941pwkb1?

my dishwasher quit working on the heavy and pots and pan cycle. no lights will come on. sometimes the
light wash light will go on along with the rinse cycle.
but, now the delay light is on. also, when it goes on
the light cycle for a few min. then goes off. what could
this be? the panel or a switch of some kind. we have
turned all the power off to the dishwasher, for a short
time, still it did the same thing.