My '09 Sport (140K miles) just developed a strange behavior. Both of my remote keys suddenly will not lock the doors. The remotes both still work fine for unlocking, and I can lock the doors by pressing the button on the inside armrest, or by inserting the key in the lock and turning it. So, it's just the locking function using my remotes that doesn't work. And since both remotes started doing it at the same time, it seems unlikely that the problem is with the remotes or the batteries.

Any ideas on what might be causing the car to not respond to the lock signal from the remotes? Thanks!

 

I think the doors won't lock if one door is open. So maybe the door switch? Does your inside light turns off when you close the doors?

 

Thank you! That was it. My interior light hasn't worked in a number of years (probably just the bulb) and all four doors looked like they were closed. But I just went out and opened and "firmly" closed all doors and now everything works.