Wont start

1998 doge caravan 3.0L has 130,000 miles for a month it has cut out when driving. The speedo and tack would drop out and motor would die. It always start back up before but know it wont even start. When you turn switch to the start position starter will not turn over. Traced all the wires back and found starter relay not firing. Have power to pole #30 and the conection to pole 87 is fine to. I also have power to pole 86 when switch is in the start position on the coil side of relay and but believe the ground side of the coil that goes to the power train module may be the issue. Is there some thing coming out of the power train module I need to check