Hi All, I ended up calling Hyundai to find out why this happened. The guy I spoke to said that if the Halo is still switched on, (car automatically locks when you hit 40kmh...in Aus anyway) that when you do stop the car as we have, not actually turned it off but just jumped out to do something, if when you open the door, you don't pull back on the door handle enough, sometimes the door will open, but won't actually dis-engage the central locking. However, he said that the boot should still have been open, which in my case it most definitely wasn't. Therefore he seems to think that my central locking is playing up. He said the best way to avoid this happening is to take the car into a service centre and have them switch the Halo off. I kinda like the Halo thing though. I have a 3 yr old nephew who is very inquisitive, and just for safety aswell. So that's kinda annoying. What was even more annoying is that even though it was something in my car that was faulty and the car is still under warranty, Hyundai will not refund any of my costs or even just the emergency call out fee, because Hyundai's warranty doesn't cover you for inconvenience.
How convenient...

"We have this auto-locking feature that other manufacturers have been using for years, but if it isn't working right then we suggest you don't use it" What a load of crap. I'd escalate the issue, something's not working right, get it fixed.

Help! Our 2010 elantra just locked us out of the car we have both remotes, but they are not operational in this situation. the key is in the ignition on off. I got out to put the wipers down and the door closed. all the doors are locked can you give us advise on what to do?

Don't you have a spare key? If you have 2 remotes, I'm assuming you have 2 keys.

no, one key two remotes. I would not be on this forum if i had 2. I'd be driving happily down the road. LOL!

update we got the car open! the battery was dead, even though the key was in off position. the remotes did not work
even after the key was removed from the ignition. so... is there a malfunction in this car? We are charging the battery now.
the remotes are woring again now after the charging of the battery.

Another question, can we get the laser key copied so it only opens the door?

It sounds like you're going to have to call a locksmith.

Man I know how you feel
 

Well s**t now you know huh I made that mistake before 250 miles from home at a McDonald's parking lot in Los Angeles YEAH I HAD TO BREAK MY DAM WINDOW TO GET IN MY CAR cause I had no money for a tow man to open my car.My moral of the story is I now take my keys every time I exit my car YUP.

What you are missing is that the car is doing this sporadically! And it shouldn't be! I have a 2017 Santa Fe that does not normally lock at all. The car can sit it the garage for days and never locks on its own. Twice I have mistakenly left the keys in the back while unloading groceries and the car has locked me out the second I close the hatch, even though all doors were open. It has even locked with the keys in and the car running. It is a DEFECT!!! And putting the blame on the driver that they don't always carry 2 keys is BS! Hyundai should fix the problem! What if an infant was in a car seat in Phoenix in July and the car locked itself? My neighbors have the same vehicle and it has happened to them also.

I agree and this needs to be checked out by someone that knows how the system is supposed to work and verify if it is.