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I have a 2000 XLT that the passenger side back door will not open. The locks were sticking for a couple of weeks and then the warmer weather seemed to make them work right for a few days. Now the lock button comes all the way up, the handle seems to be engaged but i can't get the door to open. I got inside the back and with the lock up and holding the pull handle open tried kicking the door open but with no luck. How do i trouble shoot this? How do i get the inner door panel off when i can't get the door to open? Do i remove the small left seat to start? Please help as this could pose a dangerous situation as i cart my 2 boys around.