I have a MAYTAG MDE8400AYW with the same problem as many others - my timer does not advance or shut off the dryer (Neither in the timed or moisture setting modes). From all that I've read, it seems that Maytag / Whirlpool created a NIGHTMARE when it comes to replacing the timer for this model dryer. There are at least THREE timers listed, each with different connector configurations. Some people claim that they have been advised that they would need to replace their wiring harness in addition to the timer.
Even the APP techs seem to be perplexed by the situation!!!
My serial # is 23219893EEC - a "Series 23"? Unfortunately, I've not seen any timers listed specifically for a "Series 23". And NONE of the numbers listed below the barcode on the three timers listed on APP match (exactly) the one on my timer - although one is fairly close.
A rep on the APP chat said that based on my model# & serial#, timer AP4042974 would work. Is there any way to confirm that the wiring code configuration for this particular timer matches the wiring code configuration of my timer BEFORE I purchase it? Thoughts? Suggestions? (Yea, I already thought about throwing it off a bridge, but can't afford to right now! ) Thanks

HELP PLEASE. THANKS

You need a series 16 timer. My understanding is the problem raises its ugly head when you hit series 24 and Maytag was still using series 16 timers and wiring harnesses in some of the units. You should not have this problem. If you have put in the wrong timer you better check the electronic dry control board. The timer motor feeds this board coming in on the brown wire.