This is the 2000 Durango you just got, right?
Gotta have an OBDII scanner.
Yes, it's the 'network' for all the computers in the car. They have 2 networks now, the CCD and SCI.
You will know more once you get a good battery in it and see if you can get any more codes.
Read the beginning of the BCM book on communication, and in the service manual. It will help.
IF there are any other tips like the one about the crank sensor, those are often easier than trying to diagnose it. IATN is good for common faults.
Do clean all connections that have been sprayed. Rusty coolant tends to make real nice connections where ther eshouldn't be!
Also clean all computer connections.