Welcome to the forum!
My experience with the ACE macerator is that it usually blows fuses when it is blocked somehow. I would check the hose first and then maybe see if there is hair or something wrapped around the macerator (it is like a big blender and can have something wrap around it). Luckily, the ACE is set up to be able to dump manually but you have to pull up on the passenger's side instead of the drivers. Once you take off and drain manually, you can check to see if it is obstructed.
I usually put the macerator hose in the dump station, open it, turn on the macerator for a second or two to come up to speed, open the black and let it drain. Then open the gray while washing additional water into the black. Then close the black when empty and add water and digester. Then close the gray with the macerator on for a second or two to help drain. Then shut off the macerator and manually lift/manipulate the hose to get it fully drained before shutting off at the end and removing the hose from the dump.
There are a number of threads about the macerator and the ACE on the Thor Owners forum. Some also suggest using a 20A fuse in place of the 15A, but I would be careful doing that.
Colorado '15 Winnebago Forza 34T w/MKZ hybrid toad