Your symptoms point to a failed bucket switch, a wiring failure or a bad control board. The switch costs about $6. You may try replacing this component first to see if that resolves your problem. You can order the switch from the
website. The part number for the switch is 6600A30003C. If you replace the switch and still have problems, you can check the wiring between the switch and the control board. If the wiring is okay, you will likely need to replace the control board. The wiring diagram and disassembly procedures are shown in the image below.
If you do not feel confident repairing this problem yourself, then you can have it repaired by a Sears technician. Here is a link that will provide the nearest drop-off locations:
Sears Home Services