k1rod
New member
So my 22 year old Maytag Neptune MAH3000AWW (Series 18) started acting up recently. Sometimes it would run through a cycle but more and more often it would either not spin out at the end or the timer would stop advancing and the machine would stop mid cycle. The first thing I did was to check the door latching mechanism. There are two switches in the mechanism that are actuated by the wax motor that tell the machine that the door is locked. If the machine thinks the door is not locked, it won't spin out. I pulled the switches out (they both are the same part number #22002162, normally open switches) and tested them with a multimeter and they are both bad! One measured several hundred ohms when depressed and the other switch measured in a range of several hundred Ohms all the way up to MegOhms when actuated repeatedly. I shorted the leads of my meter to make sure it was working properly and it was. Both switches are bad so I replaced them. Problem solved, right? So I button it up and a couple of days later I'm washing clothes and the machine doesn't spin out again. Well this is annoying.. So I open the machine up and look it all over again. The wax motor is working, both new switches are being activated, the door lock light is coming on ect... When the machine does pump out, the water flows with a strong healthy volume so I figure the pump is OK and that there is no blockages in the hose. Hmmm. Maybe the out of balance circuit is acting up. This machine has three switches in the out of balance circuit. They are all normally closed and wired in series. If anyone of them opens up, the machine aborts the spin until the circuit is closed again (at least this is the way it is supposed to work). I pulled the switch on the rear strut and it was working fine. Checked the tub deflection switch and it was fine too. The inertial balance switch, not so fine. It was open. If I shook it really hard I could get it to intermittently close but that's not the way this switch is supposed to work. So I replaced the inertial balance switch part number #22003302. But in the back of my mind I'm thinking... If this switch is open, how did it ever spin out? After doing a bit more research I learned that firmware on the control board that controls the spin abort was revised somewhere along the way. In the original version, the out of balance circuit didn't have to be closed, it just had to not change state. So the machine would sometimes spin out so long as it didn't shake hard enough to switch the state on the defective inertial balance switch from open to closed. The firmware was eventually changed to abort the spin if the circuit ever became open. Anyway, buttoned it back up and ran it for another week or so before the machine stopped again. This time it was the other issue where the timer just stopped advancing and the machine stops mid cycle. I've checked everything else so I'm thinking my control board was flaky. I have several spares so I swapped it out and the machine is now back to rock solid performance.
My takeaway from all of this is that these switches don't necessarily fail completely all at once. They degrade. The door lock switches can develop resistance and still work because the impedance of the control board circuit that monitors them is high. I have three spare parts machines and I checked the door lock switches in those and 5 out of the 6 were in the process of failing too. If you have one of these machines, check those switches. Good chance they are going bad. The other take away from reading and measuring the parts on my parts machines is that the inertial balance switch is more likely to be bad than the tub deflection switch or the strut switch.
Hope this helps somebody.
My takeaway from all of this is that these switches don't necessarily fail completely all at once. They degrade. The door lock switches can develop resistance and still work because the impedance of the control board circuit that monitors them is high. I have three spare parts machines and I checked the door lock switches in those and 5 out of the 6 were in the process of failing too. If you have one of these machines, check those switches. Good chance they are going bad. The other take away from reading and measuring the parts on my parts machines is that the inertial balance switch is more likely to be bad than the tub deflection switch or the strut switch.
Hope this helps somebody.
