No life in one servo

I was testing my robot this morning and discovered that the shoulder servo isn’t responding. I tried plugging it into a different pin in the SSC32 servo controller(and changing the pin number in the code to accommodate this), but it still had no life. It’s a heavy duty servocity servo and it’s worked lots of times before but a few nights ago it stopped moving all together. I thought it was the low batteries (because the other servos were moving very slowly), but after recharging the batteries, all the servos worked to full power except that one shoulder servo. All the wires look okay. It just isn’t going anywhere. No noise or anything.

What could be a few possibilities as to why it isn’t moving? I’m hoping it isn’t dead for good and I would like to get it moving again if at all possible.