Alot depends on the codes. But with any that fail when turning and since they are 7 series, I assume a fair amount of hours. I'm 99% sure your issue is under the handle. When you remove the handle assy, not just the stem, you will find that there are control harness wires that have rubbed through to the frame. The insulation on those wires is very soft. It only takes one little strand to poke through to cause issues. So if it isn't obvious, you'll need to inspect carefully.
Removal is best accomplished by removing the arm angle switch bracket before disconnection wires from switches. 1 harness plug and 3 allen socket bolts and the handle assy lifts off.