2016 won't lock. Thinks key still in car. Solved!

She can probably lock it manually with the key?

But with the FOB, is the spare key inside? I'd try starting the car, turning it off and re-try exiting and locking it. If not, lock it with the manual key.

 

If it's Ravenna ITALY, then you're right.

Long distance troubleshooting indeed.

1. If she borrowed your car and you only gave her one fob (I advise against this BTW) and that fob is not in the car, then it's NOT the fob - but it might be another fob that you left in the car that you both are unaware of.

2. Could also be an open door or hatch, or even a not-properly-shut down car.
The not-shut-down car part is easy to detect, and usually the car will wail at you if you try to lock it with a key fob with an open door (US spec cars.)

3. It's a little early for this, but you may have a marginal battery in the fob.

Tell your kid to manually lock the doors and make sure that the hatch is all the way closed and then lock the driver-side door with the keylet as advised above. If it stays locked then she'll just have to suffer the agony of not being able to remotely lock the car and you will know that the car does not think that there's a fob inside.

If the car will not lock with the keylet and you're dead-bang certain that there's not a fob inside, then tell her to put the fob in the microwave being very careful not to turn the microwave on, and then go and see if she can start the car without the key.
The microwave is just a temporary Faraday cage in case the kitchen is very close to where the car is parked, and YES, it's overkill but troubleshooting is meant to rule things OUT.

If she can start the car, then there's another fob in the car or there's a VERY interesting problem with the electrical system.
If she can manually lock the car with the lock button in the door, then it's a fob thing. If not, it's an electrical thing...like a load on the electrical system preventing auto locking or similar problem. (USB, dome light, etc.)

Let us know what it winds up being

 

Deleted. I originally read charge instead of change.

The microwave is probably loads of overkill.
She's probably good to go if she just moves the beer bottles and pizza boxes out of the way and leaves the fob on whatever is serving as a kitchen table.

 

A DVM is a good thing for a college kid to know how to use!

 

Embarrassment is always preferable to expensive repair.

 

+1.

Glad it was only cockpit error.

 

Gotta be careful about leaving the car on. If some thief comes by and sees its still on, they can get in and drive away without the key. And If you are parked in an enclosed space, like a garage, gotta be careful of carbon monoxide poisoning.