Wanted to pose this question to the group - I have a Tech2 and was trying to help a buddy program 2 new fobs for his 2012 Sierra. I was able to program my new fob earlier last week without too much trouble-although I think I did the clear existing fobs. On my buddy's truck, I was trying to just add fobs into the 2 blank spaces but got an error message indicating it could not do this task (some variation of that verbiage) and wonder if I need to clear the existing fobs from the Sierra. The truck shows 2 although he only has 1 and it is working - was able to do the key test which tells me the Tech2 is communicating. Any thoughts from the group that have done an add??? Thanks!