the same thing happend to me about a month ago....
went off when I restarted the car and has not come back on.

no idea but in the old cars it was the key (smart pass security system)

 

If you lock with the fob then unlock with the key the security will tell you about it. It's in the manual.
Don't have one, it's in the car. That's why post #2 is there.

 

i have never unlocked with key

 

I had this happen to mine a wile back. Check the battery cables under the hood to the under hood fuse box. Also if you battery is not good you could get this light on start up.

 

Update.....wife made it to work and back, no problem. Light went out when she started the car to come home.

@ Lucky;
I will check this weekend, thank you all for the comments and suggestions.

 

The connection on mine was only about a 1/2 a turn loose and over a month or so my light would come on on start up at times. It would stay on until the next time I shut the the car off.

Then one day I was leaving work and turned the key and the car just clicked one time and all the dash light went out like a dead battery.

I tighten the battery cable in the picture above and all lights returned and my car has been working great for well over year now.