Q:Finally the problem with my radio was not the icm.  If you can believe it, one of the optical wires was defective and it was giving a weak signal so the radio was not turning on.  We replaced the wire and it started working again.

A: Im glad you started working again, this is a very rare issue, you are first person to have that problem that I know of,  99% it is radio ICM unit that fails and needs to be replaced,  I would also keep spare icm because it looks like failure rate is around 100% if it goes to 03-06 XC90 series,