Chosen Solution
My iphone is completely unresponsive, it doesn’t respond to toggling the ring/vibrate switch, to being plugged into a charger, to setting the volume and is not detected when connected to a computer. Is there any way to determine whether the fault is a dead Battery or a damaged Dock Connector?
I’d start with the easiest and most economical. Change the battery and go from there. I would think that the battery is at the end of its life span….good luck