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Replacement parts for MAYTAG MDB9600AWS DISHWASHER- UNDERCOUNTER | AppliancePartsPros.com

Here is a service manual
http://appliancedigest.com/index.php?/files/file/474-16021814-maytag-jetclean-ii-dishwashers-service-manual/

You may have to join the site to down load the manual but it is free and a good site to belong to.

Check behind the kick plate to see if the tech sheet is there. It should give the pin-outs for the keypad/control panel. Then you could check it with a meter to see if the switches are OK.

Your problem can either be the control panel (Keypad) or the control board.
Without a keypad wiring diagram it is a crap shoot as to which one is shot.
Check all the keys to see if any other keys work. The reason that you do this is most keyboards use a common line for a number of keys so if that line breaks you loose about 3 keys. If this is the case I would replace the keypad first. Still not 100% that it is the keypad but your odds are better.

I would try the following before ordering anything.
Connector Cleaning / Checking
Unplug the unit
Open it up
Remove the ribbon cable from the keypad to the control board at the control board.
Clean the edge connector.
If it is the type where there is not a connector just the insulation is removed, it can be cleaned with a pencil eraser. Do not use an ink eraser as it is too abrasive.
Check the tracks in the ribbon cable for hairline cracks. A magnifying glass helps here.
Would not hurt to clean the connector on the board. Use electronics contact cleaner or isopropyl alcohol and a tooth brush. Be gentle and do not reconnect till all the solvent evaporates.
Reconnect everything and give it a try.