Place a 2500 set on the port at the frame and call it. If it does not ring, then put a volt meter on tip and ring, set to ACV. Call it again. You should see ~90VAC. It could be a coincidence that the port is bad or the RGU part of the PSU went bad. You could alo try resetting the circuit card. They are hot swapable. Press the reset button, or pop it out, then back in.