The 2 most common part(s) or condition(s) which cause the symptom Washer door or lid won't lock are listed below starting with the most likely. Check or test each item and watch any available videos.
RepairClinic Item # 1094190
If the washer lid or door won't lock the lock and switch assembly might be defective. This is a very common problem. The lock and switch assembly can fail either mechanically or electrically. Test any electrical switches with an Ohm meter for continuity. The switches should have continuity according to their design.
RepairClinic Item # 2071402
If the door won't latch, the door lock assembly might be defective. These are normally made of plastic and cannot be repaired. If the door won't latch and the door lock is broken, replace it.