Had the same issue and SC claimed 2017.38.4 fixed it, I am on 2017.40.1 now and no recurrence yet.
It's pretty simple to do;
1. Open front trunk
2. Remove plastic trim cover at top edge (closest to windshield, the black plastic piece with the tag coming form under it). It pops right off easily, not held with standard trim clips and designed to be removed.
3. On left side (facing back of the Model X) is the battery. It is slightly recessed so a little painful to reach, but not tough. Disconnect RED hot lead and leave disconnected for a few minutes and reconnect.
Note this will reset the car including the FWD and you may show door errors. Opening and closing them will reset them and clear the error.
Thanks. Will give that a try. The tech had me disconnect the ground lead... nothing... the car acted as if the battery was still fully connected.