Does a Mark III have a "death cap"?

My Mark III has a ground-mode switch. For what it's worth, I've never noticed any difference in sound or noise regardless of what setting it's on, so it might not even be hooked up anymore. Anyway, isn't a ground switch like this a sign that the amplifier has the so-called "death cap"? Should I be looking into this and confirming that it's been changed to a more modern grounded design? It may have been done already, the power cord is a 3-prong grounded one.

Yeah, the "death cap" is referred to those old Fender with 2-prong AC cable. Since then all modern amp due away with the "death cap" - well that I know of and I'm not an amp tech, just that I replaced my Fender Princeton with a 3-prong.

The ground switch was needed in the old two-prong cords, so an upgraded three-prong cord would eliminate the switch and the need for the cap. Even if the cord is replaced and the cap removed, make sure the fuse is on the hot AC lead, not the ground (as Fender used to do). Otherwise, the fuse could blow and the amp could still see high voltages.

There are other caps in amps that see/store high voltages, so unless you know how to drain them, proceed with extreme caution!