I have a 1999 chrysler town and country van. Recently swapped a 3.8 for a 3.3. Then had a bad left front wheel speed sensor. Changed that and brought vehicle in to have abs light reset. Found out there is no communication at scanner and obd2 port. Unsure if this problem existed before engine swap or not. I am looking for any ideas on where to start to fix this problem or where to get the wiring schematics to start tracing wires back from the obd2 diagnostic port. Thanks

 

You might want to buy a shop manual for the car. It'll have full schematics. Surprised you have done all this without one.