Hi Pcan and welcome to the forum. For your peace of mind, on your Elantra it is normal for the marker and taillamps to be illuminated on daytime running light settings. I guess the gurus in Korea thought if having the headlights on all the time make you more noticeable to oncoming traffic, there is some merit in having you more visable to traffice coming at you from the rear or sides. All late model Hyundais operate that way.