Unlock a BCM?

I have to put in a used body control module in my cav and when I hook up my scan tool (It's the Tech 2-same as the dealer uses) It says I can't do anything because the BCM controller is Locked??? I'm never heard of this on a BCM. My scanner says consult the service manual for instructions but of course I don't have a factory service manual and my dealer will not tell me how to do it. "bring it in and we wil fix it". Yeah right. Any help out there??? Thanks

yea bring it to the dealer and let them fix it :)