There would be two common reasons for the washing machine not going on the spin.

1. Door Switch (Sensor) Malfunction or door not closed properly.
2. Unbalance the drum while spinning.

Check the door if it is closed properly or you must change the door switch or door sensor.

Do you have an overloaded or unbalanced wash load?

Another normal issue that causes the clothes washer drum not to turn is having an over-burden drum or lopsided wash load.

Having a lopsided wash burden can confound the clothes washer’s sensors and keep it from turning. Guarantee that your wash loads have an assortment of things in various sizes and don’t wash bunches of huge towels in one go.

Additionally, ensure the clothing you have placed into your machine doesn’t surpass the weight in the furthest reaches of your clothes washer

In the event that a top burden washer’s tub starts to beat against the sides of the washer when the twisted cycle starts, this demonstrates a logical lopsided burden. Simply stop the cycle and mastermind the garments in the bin and attempt once more. Notwithstanding, if no measure of adjusting revises the issue, there is a high likelihood that a mechanical issue exists.

Conclusion

Now if your machine is displaying U4 after a cycle this indicates an unbalanced error, which means you should put similarly weighted items inside the drum otherwise it won’t spin correctly.
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