Prior to the last time the dishwasher ran, it required several attempts to start it. Symptoms included the wrong LEDs lighting after a button was pushed, a faint rapid ticking sound somewhat like a Geiger counter, and all of the lights blinking simultaneously. After repeated attempts, the dishwasher finally started, and operated normally. In the next attempt to run it, the cycle started briefly after a couple tries, accompanied by the clicking/electrical noise, LEDs faded out and back (along with the noise), then no response at all.

Browsing this forum, I've found parts breakdowns and manuals for many other Maytag dishwashers, but not for the MDB6650AWQ. I'd be deeply grateful for any pointers.

Here are your parts includes a wiring diagram
Replacement parts for MAYTAG MDB6650AWQ | AppliancePartsPros.com

Check under the unit and on the back of the kick plate for the tech sheet.
I could not find one on line but perhaps someone else will add it.

It sounds like the control board is shot.
I would open it up and check for loose/poor connections at the board.
Also check that the wires from the board going under the unit are OK.

It could be something is pulling the supply voltage down.
Check the voltage to the unit with it off and then on, should be close to each other 120 volts approx.
Unplug the motor, dispenser and vent to see if it will now start.

If nothing makes a difference then odds are high that the board is shot.

I couldn't find one under the dishwasher or behind the kick plate, either. Fortunately, I didn't need it.


Bingo. My very first glance at the first of two boards one sees inside the door (it appears to be the low voltage power supply for the actual controls) revealed a capacitor which was not soldered at one end. (I saw no evidence that it had ever been soldered, actually. :confused:) Apparently, slamming the door during numerous attempts to diagnose the erratic behavior had jarred the capacitor's lead out of contact with the trace on the circuit board. I resoldered the lead, and the dishwasher has now washed three loads without any problem.

Thanks again for the help. :)