My left rear door has ceased opening. This happened today in the middle of an errand trip. I pulled up on the door lock to unlock (my vacuum locks have not worked since I got the car) and the knob came up free in my hand. After getting the kid in the car seat from the other side I tried opening the door from the inside. No go. The interior door handle moves but does not catch or actuate on anything. I figure I have to take the interior door cover off to see what is happening to the mechanism, but I have to open the door to do that. Are there any tricks to opening a door that won't open with the door handles? Thanks.