Hi Bzargtar,
I had a can bus error which turned out to be a bad splice in the engine compartment. I went through a lot of troubleshooting before I found it which I documented in this post: no crank, black rectangel/square in the IC - CrossfireForum - The Chrysler Crossfire and SRT6 Resource. The easiest way to verify if your can bus has issue, is to measure the resistance of the can bus circuit at the PCM (ECM) C4 connector, between pins 1 and 11. If you back probe that connector (i.e., leave the connector connected to the PCM and touch the probes to the back of the pins in the connector) you should measure around 60 ohms. If you measure an open, a short or 120 ohms, you either have a broken wire (usually very hard to find or fix), or a bad termination in the SKREEM. If you have any questions regarding the troubleshooting steps I took, please ask.
Good Luck,
-Jerry