I have a 2005 9-3 Aero and the ICM3 unit has stopped working. The SID continues to work, but am getting no sound for parking sensors, indicators etc. Main screen does not turn on - any suggestions on what I can check to find the issue?
It's probably a fuse. Also worth seeing if your passenger side floor is dry as sometimes leaks fry the amp under the seat. Erosion also causes issues with Amp1. If it fails, the fibre loop is no longer intact and will cause some of the symptoms you're experiencing. The fact the screen isn't turning on would suggest a fuse though.
I don't have a fuse diagram handy, but the fibre loop goes through you ICM, EHU, CD player, Amp1, Navigation system, and Amp2 if you have it. If any of these items have a blown fuse, the fibre loop will be broken resulting in these issues. Check fuses for all