This morning, Sunday, I made the decision to wash the car Hyundai i30
So I unlocked it, went for the bucket and the car locked
Unlocked it, and went for the hose, and the car locked
Third time I recorded it, unlocked the car and 32 Seconds later it locked

This could lock me out of my car???? I wrote to the service department for an answer
Now reading this site, I know THIS IS A COMMON PRACTICE - with no response from the company's service department.

Then I had a thought, I unlocked the car and opened the driver door for a few seconds and it DID NOT LOCK but you inform me of the fact;  if I were to accidentally leave the car unlocked in another location such as a shopping centre miles away from home; this could happen again isolating with no spare key.

I am glad to find an answer to know I'm not going M A D, but sad to learn it is a dangerous act for a single lady miles from home living in an isolated area.

[PhireSideZA]

Mine has the same behavior. I think it is so that if you accidentally unlock your car while in range (pressing the unlock key whilst it is in your pocket etc.) and no door gets opened it will lock itself again as the car would see it as an accidental unlock.

I have yet to try and lock the car with the spare key in the ignition and then unlocking to see if it will lock itself again after 30 seconds, but maybe someone else on here can shed some light on the topic?

[Dazzler]

Welcome Cheryl,

This auto locking thing is quite common now, not just with i30's. My late Model Holden Calais also does it. I think you may be able to turn it off, but have never tried. My key stays in my pocket at all times. Proximity locks and push button start, but certainly more risk of a lockout with normal keyed ignition.

[Asterix]

Normal behaviour, and you won't be locked out of your car.

If you unlock but don't open a door, it will lock again.

If you unlock and open a door it will stay unlocked... 

[eye30]

That issue is detaiked in the handbook.

Press fob to unlock but no door or hatch opened it will relock.

[FatBoy]

All of our recent cars have this feature.  You cannot lock yourself out of the car.  As others have said, if you press the unlock button and then open a door or the hatch, then the car will stay unlocked.  If you don't open a door or hatch within approximately 30 seconds of pressing the unlock button, then the car will automatically lock again.

[Dazzler]

Just don't use the kitchen taps if you have left yur keys in the car. ..

[The Gonz]

Same with my rented Toyota Kijang, and I do my best to keep my tongue pointing to Mecca when unlocking it in case we run out of water.