Eastern,
I think you answered your own question in your last post. You did say, "Belts", so I guess it's a late model HD operator. If so, It's a timing issue. I believe the controller has to see (in the open cycle); OFF of DCL first, then HWIL then GL, but the timing can't be all bunched up. That's why you can hold the fault back by manually stalling the operator for a moment. You're artificially creating a greater time lag between these three inputs. Either change the door open adjustment like "Open Backlash Time", or visually check the sequence of DCL, GL, HWIL to make sure the locks aren't opening before or at the same time DCL goes away. Could simply be a limit collar adjustment.