Engine missfire

2003 Ford Escape 4WD, 62,000 miles, 3.0L Duratec Engine, 6 cylinder, 4 speed automatic, full package of goods

Engine runs rough at idle, got a dtc code (ignition coil c primary/secondary circuit) it is missfiring on that cyl. All the time, I replaced the spark plugs (Requires taking intake manifold off) checked the coils, there is no problem with any coils, but there is no signal from the wires to the coil. Followed the wires back and tested for open circuit, no open circuit, so I think the problem is in the PCM (powertrain control module). Any ideas out there would be appreciated.
Thank you.