I took my car out of the garage today, and I opened the trunk with my remote, closed the trunk all the way, and then went to open it again. When I tried that, the remote wouldn't open the trunk, and trunk button inside the car doesn't work either. Neither of my remotes worked. I also tried disconnecting the battery to reset it, and that didn't work. The 'trunk ajar' light is lit as well. Is there something else I can do before I take it to dealer?
I think it is possible that you may have shut an object of some kind in between the trunk latch and the trunk lid when you shut the trunk. If an object becomes lodged in the correct spot, this can cause the trunk ajar sensor to set the light off on the dash even if the trunk is not open.
Also, if something is jammed in the right spot, this can prevent the key from being able to turn the latch from the inside. As for how to get inside the trunk if this is the case, my best recommendation would be to have an inexpensive spare key cut to the same specifications as your trunk key and try to force the key to turn; this way if the key breaks off, it will not be the main key that you need to start your vehicle.
This issue can oftentimes be fixed by forcing the key to turn. The worst case scenario would be a broken key and a broken trunk latch which are both replaceable. Forcing the key is almost certain to get the trunk open. It is quite unfortunate that this method has to be used but oftentimes it works if something is indeed lodged between the latch and the trunk lid.