It is that pesky ribbon connection. I am uncomfortable with that connection. I pulled the panel out, and followed the suggestions for cleaning all contacts in each connector. I tried to burnish the contact edge of the ribbon, I used a white eraser to burnish, and followed up with a contact cleaner pen. I wiped the edge dry, and reinserted it into the connector block. The first attempt did not fix the SE error problem. Second attempt, I used an acid brush (a brush used to clean new solder connections) dipped in alcohol, and forced the bristles directly into the board connector, then wicked away the excess liquid, following up with a canned air blast. Finally, when I reinserted the ribbon, I worked it in and out a couple of times before locking the connector. That worked.
I am completely underwhelmed with the quality of workmanship, and the non-robust design Samsung put into this appliance. I am now worried that our Samsung stove-top/ convection oven combo is headed for troubles with its electronics. I suggest to anyone shopping for a kitchen stove, or overhead mount microwave, to steer clear of anything that has smarts, and is gadget loaded. Get a gas oven, with the only electronics installed being those really cool piezo-electric igniters. Really. Go for robust, but simple. Kitchen appliances go through a lot of Hell!