|I love the basting stitch on my Bernina 180 - nice long stitches, much longer than setting the straight stitch to the longest length, and they're very easy to remove. But I don't use the basting function very often and when I do, my machine can get stuck in basting mode which requires a trip to the dealer for repair. It's usually in need of a good cleaning by this time anyway, but it's still annoying to lose the machine in the middle of a project.
I asked the repairman if I needed a new basting mechanism and he said no, the problem is that I'm not using it often enough which is why it's sticking. (I sew both garments and quilts, and never use the basting function during the quilting phases.) To keep it running, you need to use the stitch every so often, even if it's just for a few seconds once a week. The same basting mechanism is used in many of the Bernina models, so if you've had this same problem this may save you a trip to the dealer, too.
He also told me that you can sometimes unstick the machine when it's stuck in basting mode, by running the machine at full speed for a minute or so. (You don't need a needle or even a foot on the machine to do this.) It didn't work for me last time, but it's certainly worth a try.