I have had problems getting the rear driver side door to completely unlock and open ever since i purchased this vehicle. occasionally the rear passenger door would do the same. i have even had the front passenger door behave this way. i am writing now, because the rear passenger door almost never unlocks and opens anymore. with both back doors not unlocking and opening, it concerns me greatly that this is a serious safety hazard should i need to immediately gain access from the outside or the rear passengers need to get out from the inside. the only way to get the doors to open is to pull up extremely hard on the door lock posts. *tr