I Evernote this from another post:
Run Forever, Turns on By Itself, Continues to run.

Compliant: Customer started a wash, left the house, came back home 5 hours later and washer was still running. Later that night she said that as they were watching tv the washer started up all by itself.

 

This washer was stuck in the "Endless Test Cycle". Tech Line said that this is used to test the washers before they leave the factory.

 

Tech Line said that if this was a new washer it would simply mean that someone at the factory forgot to take the control out of the Endless Test Cycle. However, he said that for the past year to year and a half they have been seeing these washers putting themselves into the Endless Test Cycle and the Engineers are stumped as to why this is happening.

 

To turn Endless Test Cycle On or Off:

 

Put the washer into Diagnostics, turn the dial to the LEFT (counter-clockwise) until the Wash- Rinse- Done lights are on. Push Start. If the washer powers Off you have just taken the washer OUT of Endless Test Cycle. If the washer starts to Fill you have just put the washer INTO Endless Test Cycle.

 

If the washer powers OFF, unplug for 5 seconds, plug back in and wait 10 seconds, if the washer does NOT start to Fill you have successfully taken the washer out of Endless Test Cycle.

 

He said that they have also been seeing replacement Control Boards leaving the factory that have not been taken out of Endless Test Cycle. He said that if you replace a Control on these washers to go in and check to make sure that Endless Test Cycle is indeed turned off.

Source: wtw4800bq0 Whirlpool