Its worth at-least troubleshooting. Considering a new washer of the same caliber is at-least 700 dollars or more. From reading your post, it seems like your on track. The lower off balance switch is wired in series with 2 other switch. When ever i get a no spin call on one of these machine's and the lock light comes on, the first thing I check is those switches. You can roll the control panel down to check the whole circuit. There are 2 blue wires that come up threw the top on the right side that are hooked into some other color wires with a quick disconnect. Disconnect that plug, and make sure you have continuity threw the blue wires. If it is a open circuit, then you can check each switch by themselves.