I've had this intermitant issue since I bought the van a couple years ago. Sometimes (maybe 1 out of 10) the passenger side door has problems closing. Sometimes it moves to a few inches from the closing point then will stop and return as if there were an obstruction. Sometimes it will move the closing point and sit there and make the whirring sound much longer than normal - maybe for 5-6 seconds instead of the usual 2 seconds and it won't lock, just stays ajar and you have to manually open it again and try again. Most times it closes normally.
Also, sometimes the rear hatch won't open - you hit the button and it just pops open but won't raise up. Most times it works fine.
Poltergeist? or does anyone have a clue why this happens?

 

mine does that too?