OBD II port issues

I just picked up a scanmaster and cannot get my OBD II port to work with my car. The unit will power up and show the versions but goes dead after that. I just checked it in my buddies car and it works great! I pulled the panel down and removed the plug and found everything to be ok with it. Does anyone have any advice as to where to start the troubleshooting process? I know the port has power as it starts the unit fine. After talking with the Scanmaster on it they thought my port was bad. How can I verify this? Is there a pin on the computer that I can check continuity with the wires on the port? I'm guessing if I did that I should dis-connect my PCM first? Any help would be great! My biggest reason for posting this in this firum is that I will be purchasing EFI Live and V2 scanner in the near future and would like to make sure my port is functioning correctly.

Need a wire diagram;
check for 12V and ground at pins shown in wire diagram;
disconnect battery;
disconnect PCM;
use ohmeter to check continuity;

Do NOT ohm any circuit while battery or PCM is connected.