[JonathanLipan]

I bought a 2005 STS and it came with one key. That worked great, remote start worked, everything worked. Then I managed to find another fob at the junk yard. Using the physical key, I managed to pair that fob with the car, but the car said that that was now fob number 3. The problem with being either key number 3 or 4 is that they won't activate some of the features of the car, like remote start. I made sure to enable remote start, and save the settings to the driver selection with the key (key #3). To solve this issue I had to go through the 30 min process to delete all previous keys from the car, and then reprogram my current keys as key 1 and 2. Now remote start works correctly on the "new" key. I hope this helps someone else who is confused as to why their key just doesn't use all the features of the car.

 

[ECha3]

You'll need to rematch both fobs to clear the old fob 2. Only those matched as 1 & 2 hold personalized settings required for remote start.

The instructions are correct but there's a trick. Keep both fobs very far away from the car until requested by the car. If any matched fobs are within range of the car, it won't start matching with fob 1.

FYI - The matching procedure changes both the fob & car.