Keyless entry not working

Keyfobs don't work anymore, have tried the instructions at the top and to no avail can I get them to program. Since the instructions I now do not have automatic unlock of doors when you put it in park. I have checked the batteries in both remotes and they are good. Please help....... Is there any other tool than the TECH II to program stuff like this? Maybe Snap-on's scanner or something. I worked at a gm dealership once and know what it is but they are very expensive....