PCM 2.1 Hardware Dead or Software Corruption?

[Zuffenhausen955]

My SAT radio and PCM 2.1 is stuck in some kind of "boot loop mode" and refuses to properly power-up. I do the 1/4/8 keypad reset and only the Porsche welcome screen comes on for about 28 seconds....then blacks-out. No sound heard whatsoever. Prior to this occurring the PCM was coming-on by itself randomly. 

Two peculiar things I noticed:
a) No buttons on unit illuminate, day or night. 
b) Dash center indicator shows NOTHING... not even "Radio Off, " or GPS dash Compass.

c) I am suspecting the instrument cluster and PCM are no longer communicating.

Edited April 9, 2017 by Zuffenhausen955

[hahnmgh63]

Might try disconnecting the MOST connection from the back and then try to boot it up to see if there is a difference? It would rule out that something else on the MOST bus is the cause.

[Richard Hamilton]

Try removing the navigation disk, just in case it is having trouble reading it, causing the re-boot.