2009 GT - Key fob doesn't work after the battery is replaced

[jasoki]

We have a 2009 GT with two keyed fobs, purchased second hand from the original owner in 2014. Both fobs worked just fine until last week when one stopped remotely locking and unlocking the car. It will start the car. The other fob is still going strong.

We replaced the battery in the non-working fob but that didn’t fix it. The light does work. We went through the reprogramming steps (door opening, key in/out, etc) and tried to “add” the fob but the car was saying that they fob was not accepted by locking/unlocking its doors twice in a row. We did this a dozen times and it’s unlikely that we were making errors with the sequencing, but it is possible.

Next we checked how many fobs were programmed in using confirmation mode and found out there are actually three. We’ve only ever had two so we figure it’s the two we have and then a mystery one – lost, stolen, previous owner, who knows? But it’s indicating to us that the non-working fob is still programmed to the car, it just won’t lock or unlock the doors.

We’re debating resetting the whole thing and trying to re-add both but are afraid we won’t be able to reprogram the one that’s currently working. Any thoughts or tips before we nuke the programmed fob and try to reprogram?

Thanks,

[VibeNation2024]

I have an 2007 and 2008 so don't have personal expirience with your issue. There are some previous threads that might help such as viewtopic.php?t=46844 and then sub links in there.