How to fix a maytag 300 dishwasher latch that won't latch?

SOURCE: Maytag Dishwasher Latch Sticks

John, I had the same problem and just disassembled by removing the dozen or so screws around the inside of the door, lifting the waterproof panel, and pulling up the latch assembly to see what was broken. In my case there were plastic pieces broken off of the latch handle and where the latch hinges on the back of the control panel-the latter piece is $50 to replace. unfortunately. Good news is the disassembly and replacement will be easy as a DYI. Sorry this is too late to help you, but maybe others will have the same problem. Bruce

SOURCE: maytag dishwasher latch

If it like mine, the latch is out of adjustment and you need to give it a whack with your hip to start it. If I adjust the latch looser, it leaks.

SOURCE: Maytag Quiet Series 300 smells broken door latch and lower rack

I have had the same problem and there is a simple fix.

The problem in my case was the floating water sensor was stuck and gummed up with grease.

On the bottom of the dishwasher, in the front right corner there is a round doughnut-looking thing. This is the water level sensor. It is open on the bottom, and grease collects there.

When this happens, the air pocket is too small, and the float won't float. then the dishwasher overflows. To clean it: just reach under with your finger, and scoop out the grease.

Sometimes, after doing this, the float then gets stuck in the "up" position. When this happens, the dishwasher completely drains, and the heater element for the dishwasher is exposed, and food cooks onto it, and that is where the smell is coming from.

SOURCE: The latch is sticking on my dishwasher. How can I

replace the door latch and the handle check to see if the console loops that hold the latch are broken if so replace the console

SOURCE: Latch on dishwasher was broken,

You'll need to check the ribbon cable between the keyboard and the circut board and any switches controled by the latch which is more likely the problem.Also look for a loose wire on or near these switches.
Good luck,
Mastatech