The new radios are ran by the data circuit in the car. Sometimes there can be too much clutter on the data line and the BCM didn't get the message through to the radio to turn on. I had a couple of devills with the NAV radios just stop working. I couldn't get them to power up with the scan tool or anything. I simply unplugged it and plugged it back in and it came back to life. Everything on cars today is a computer and sometimes like your home computer they simply need rebooting.