twood19
Diverter valve. Probably clogged just enough to keep it slightly closed. The pressure sends the water up to the shower head. If you have a pull up knob on the end of the tub spigot to activate the shower head, you can get a new one for about $10 and replace the tub spigot with the new one. Most simply screw on. It may have a hex key bolt on the bottom side near the wall. Loosen that first if there is one.
There is nothing up at the shower head that would cause it to leak.
