f 20 code??????

Hi. Kenmore can be difficult to look up information on. The tech sheet should be on the unit somewhere that will have our error code information. On this unit I would take the bottom drawer out and look on the sides inside the drawer cavity. It will be usually taped or in a bad taped to the side walls. It could also be in the control board cavity or on the back of the unit. I do not think it will be on the back of the unit since its a slide in or drop in style range. I have attached some links to some forums on this issue. They are not for your exact model but the error codes should still mean the same. I have also attached a link for the parts break down which has a wiring diagram on it as well. It will not let you look at the diagram when you click on it, but right click on the pic and then save as. Then you can save it to your desk top and view it. It looks like you have a communication error between the main board and User interface. Check your wiring and connections between the 2 boards. IF all is good then it could be either one of these parts that is bad. There is not going to be a way to determine which is bad. Look for burnt marks or corrosion. If there is a ribbon cable on the User interface check it for damage or discoloration.