Programming 2nd remote overwritting 1st remote

[dwhittenburg]

I recently purchased an 08 Yukon. It came with one keyless remote. I ordered a second off eBay. I was able to program it, but after doing so the first remote doesn't work anymore. I can then re-program the first remote and the second won't work. I know I can have two remotes. Are the remoted IDed somehow? How can I resolve this issue?

 

[greenhornet]

The second remote must be programmed within a few seconds or it wont accept it ,so start with the first one then right away do the second one.

 

[ChevyFreak]

The second remote must be programmed within a few seconds or it wont accept it ,so start with the first one then right away do the second one.

+1 - Good Answer!

Just for clarification, both remotes must be programmed under one re-programming session. Once you start the relearning process as you have done already, simply program both remotes within a short period of each other under that same reprogramming. Do not re-start the learning process between each one. Good Luck!