Question: What Happens If the Clustered Index is Disabled?
Answer: If you disable the clustered index, you can’t retrieve data from the table. Technically the entire table goes offline, till you rebuild your clustered index.
A clustered index is actually table itself. When you disable it, it will disable the access to the table.
If you want to enable the Index, there is no enable index command. You will have to rebuild it and I have to build a video about that concept here.
I have previously blogged about this concept and I have also provided the detailed script for the experiment. Here is