I have a 2000 Maytag MDB9100AWB. It's an unremarkable machine, but it cleans well and it's nice and quiet.
One day it want on strike right after I loaded it to the gills with some particularly dishes. Well I wasn't about to unload a bunch of dirty dishes and go buy a new machine so I was determined to fix it.
I took the door apart to get at the control board and found the solder joints where the relays attach to the board and all the solder appears to have evaporated. The relays were loose on the circuit board. I simply re-soldered the relays and it works like a champ.
If you have one of these machines and it refuses to start, pop the control board out and check the relay solder joints. If they look "cold" re-solder them.