On my old Bernina when the shoe is down the top tension is engaged, when its up, top tension is relieved. There is a mechanical linkage/arm that takes care of that action. I have been pressing on with my cushion project with just about zero tension issues. Took me a couple of steps to get straightened out. One.....I had to recognize the problem was top tension was not working right. Second, I think what was going on was within the top tension discs there was a bit of 40 year old built up crud and the small pin that pushed to release and engage the top tensioner was goo'd up a bit. I cleaned the disc assembly out with some alcohol and a folded edge of a an old hanky. As far as the release on, I think sometimes it was releasing thereby engaging the tension and sometimes it was sticking which kept the tension from coming on when the shoe was put down. I put a tiny bit of thin oil on it and worked that pin in and out a dozen times and its now smooth and free, where before it seemed sticky. My problems were intermittent which drove me nuts. But the good news is I think I got it solved. If you have the bottom loops I think that is top tension. But just because the setting is high, it does not mean necessarily the discs are working correctly. I have no idea about your machine but take a look when you engage the shoe to make sure there is tension on the top. That is where my intermittent problems were finally identified.