Bad grounds, and or cracked coil packs can cause issues where the charge shorts and makes its way back to the ICM which can fry it.
I have not experienced that myself, but I read about it here.
I'd get a multi-meter, set it to ohms, and check the ohms of each coil pack, the resistance should be close to the same for each, there is a spec resistance mentioned, but it was in my manual, and I lost it.. If you have a manual you may be able to find it in it.
The reason I suggest that is from what I have read, a failing coil pack can kill the ICM, that is a new one on me, but others say it has happened to them.