Dodge Intrepid No Bus

On My Obd11 Code Reader It Shows Pcm Not Recieving Messages Where My Odometer Is Reads No Bus What Could Be My Problem?

I Have A 2001 Dodge Intrepid 2.7 Throwing Bus Codes.. I've Been Told Its The Pcm/ecu. Any Way Of Telling The Serial Number Without Pulling...

I Recently Installed A Heater Core In A 95 Intrepid For A Friend. Had To Pull The Entire Dash Of Course And After Re-assembly The Gauge...