Lack of any CAN network activity with new / pending installation.

Hello,

I'm new to Murphy and CAN networks. Installing a CAT diesel driving vert turbine pump. Using a MPC-20-R2 to comm with CAT via J1939. TWIN Disk HPTO is installed between CAT and pump. Have not received the CAT or PTO yet but have Murphy and what looks to be a re-packaged/labeled PV-350/380-R2 Powerview Diagnostics Display with a TWIN Disk label on it. I am trying to connect to CAN network with ECOM2 USB to CAN interface. The CAN network consists of term resis on each end, and ECOM dongle. Network resistance shows 59ohms. When PV350/380, or MPC-20 is connected and goes thru what looks like a "powerup" routine; the network resistance goes to 3.2 Meg ohms. Power down the PV350/380 and the resistance returns to 59 ohms. Also when I start up PowerVision for Controllers and click on Edit Connection Settings and the ECOM Connections Setup shows the ECOM Serial number field is shows "0" and I can't change the value to the serial number on the ECOM Dongle. The power light is lit on the dongle but other LED's are dark. Looking for some help from the group. Windows Device info shows driver is working properly. Thanks for your time and any advice.