my passenger rear door all of a sudden wont open. When locking/unlcoking via my remote i can hear the lock mechanism move but it wont allow the door to open. when i try to open via the interior lever i notice the little block button move up & downb but not the full elngth like the other 3 doors. also, when slowing down (less than around 5 mph) and then speeding up the lock makes a noise like its trying to lock or unlock the door??? any suggestions??