Since you have a used BCM already, you might get lucky and it will be "plug & play". In 02, the BCM controls: audible warnings, auto door locks, auto headlight control, interior lighting, keyless entry, passlock, RAP retainded accesory power. It also provides the ignition on/off signals to the other modules and serial data communications. So after you try it, check that all the above are working. If they aren't, then you probably need to have the Tech II programming. Before you start the truck, you will have to program passlock. I sent you an email with the instructions for you to do yourself. If you put the original BCM back in, you shouldn't have to do the passlock again.