I have a 2008 G6 that came with remote entry but not remote start. I had the remote entry code (can't remember what it was) so all I needed to do was buy the remotes and have it programmed.
I purchased the other remote start....the one with the two way remote, and the antenna that mounts inside the car. The starter came with two remotes....the two way one, with the screen, and a regular remote starter. My question is, my original two remotes....the ones that just open the door, and don't start the car......they don't work anymore. Can they be programmed so that all 4 (2 old, 2 new) work? My dealer said no....no reason given though.....anyone have a clue if this is correct?