Whirlpool model wtw5640 washer. It will not drain or respond to any commands after it reaches the first drain cycle. It does not respond to commands until the washer is manually drained by removing the hose.

SOURCE: washer machine drains while filling

If the pump is actually coming on at all times, then I imagine this machine has a completely electronic control system ? - i.e. No mechanical timer ? - If this is the case, then the switch that controls the pump is an electronic solid-state device, or, more rarely, a relay on the board. Looks like you'll need a new power board.

SOURCE: WTW6600SW2 Won't Drain

We had the same problem. In our case a penny got down under the tub and into the pump. It caused a crack in the pump and it could not get the suction it needed to drain. A new pump solved the problem. Parts and labor to the tune of $195.

SOURCE: washer won't drain after rinse cycle

If you lay the drain hose down into a bucket does water come out fairly quickly?

If so then it is not a blockage

You may have a coin or other small object in the pump which stops the impeller turning so no pumping action

Only solution is to check if the pump is free to turn either via the filter opening or taking the back panel off (Remove power before doing so ) and turning the pump by hand (there will be a fan blade on the end which is connected directly to the impeller.

If that will not turn very easily then you need to take off the hoses and check what is happening with the pump unit

SOURCE: My Whirlpool washer won't agitate or spin . But it does drain the water.

i also had the same problem, and it ended up being the coupler. It was not hard to replace, it cost me about 19.00. I didn't follow full recomende instructions. I tipped the washer backwards. Removed the drain pump and the motor itself. Then I removed the old coupling and placed the new one. The washer is working like new...