I have a 2000 Dakota 4.7 auto. Getting ap1698 no communication "from or to" tcm. Not sure wich it said. Truck runs good but is in limp. It will shift manually from 2nd to drive but no first and o/d button does not work. With all gears boxed off like all gears are selected. I can get the box to show reverse if I try to start it in reverse but will select all gears again as soon as I let the key kick back to run. This all started after I replaced the heater resistor. The truck ran and shifted good before. I have Google and tested wires till I'm about to throw in the towel. Any help would be great. Where to start. Tia