I purchased a 2013 Ford Escape Titanium at the end of June. I am still trying to figure out how to lock the doors using the black button on the outside handle. Sometimes its seems to work by simply holding the button in. However, other times this is not the case. Sometimes it works if I try to push on the side nearest the rear of the car. Other times if I re-open and close the door, I am able to lock it by pushing on the button. Any help would be greatly appreciated. I have looked at the videos on the ford website.