Perhaps somewhere a short between the groups, so too many bulbs on a group.
If something works for 15 mins it may not be a short, it may be an overload.
You can judge the fuse. The way it is blown shows the difference between a short and an overload. If the fuse still has the melting wire but it is broken in the middle it is probably an overload. If the wire evaporated it is a short.
I had a blown fuse (overload) on CV (also left side of the pf) after many months. I just replaced the fuse which solved the problem for me.
Van Alstyne, TX
