2000 Ram Laramie SLT no bus

I am working on a 2000 Ram. The truck will crank with no start. The instrument panel gauges won't work and it shows no bus. It will not connect to the computer using my scan tool. I have checked the twisted pair of wires going to the ecm and get 2.5 volts like it should and have the.check everywhere else and get proper voltage.except at the tps. It shows .5 volts. I have check all connections and nothing seems loose or corroded. Looking for more advice on what I am overlooking or missing or even possibly a solution. Thanks in advance.