20 year old maytag stack, washer doesn't stop agitating

The bacteria in the washer part are causing the smell.
Give the inside a good wipe round with a damp cloth to remove any visible residue.
Leave the door and soap drawer fully open so that the inside dries out after a couple of days; that should fix it.

Google the model number. I had the same problem, Googled it, and found the actual turial on YouTube to fix it.

Cold solder joints are common on these logic boards.
Using a magnifying glass, inspect the solder joints on and around the transformer. A trained eye will see the crack right away.
Resolder the solder connections and retest..

It's time for a new opener.

Good day,
If you need to wedge the timer to get a normal cycle, then the timer has gone out. Suggest you replace it along with a new knob, spring and clip. The parts house will point out how to install the knob. Was/is a really good washer.

A Maytag A412 is well over 20 years old....
Best guess is a corroded upper drive shaft, the one that the agitator is mounted on. Certainly it can be called a transmission problem.

transmission out buy new washer cost to great to repair 15 year old washer

needs transmisson replaced cheaper to buy new machine

Hi..I had the same problem yesterday...the maching would start when I pushed the button and then stop..I had to push the button again to get it going..My stacked set is around 8 years old.

Here's what we did..moved the washer away from the water source and unscrewed the water intake lines..there is a little screen there...took the screen out of both hot and cold lines..one screen has some debris in it..the other was almost completely blocked..we are on a well and sometimes dirt..etc..gets in the lines..

Today no problems doing the laundry..its working like new..

maytag washer dryer stack unit , model # lse7806ace washer fills with water but won't agitate or do anything else. I had the same problem a year ago and replace the lid switch asssemby and fuse and it worked fine until now. the switch clicks when I open and close the lid and the pink and orange wires show continuity with the lid closed.