2002 T&C power sliding door problem

I got a 2002 T&C Lxi, this is an intermittent problem. Sometimes the drivers side power sliding door will click open but that is it. It will not retract open. Sometimes it will work normally as well. Funny thing is is when the sliding door will not work the lift gate will act the same, pop open but not raise up. Now if the sliding door opens successful the lift gate will also work correctly. So somehow the problem is related to both the sliding door and lift gate. Could the problem be a relay or sensor? Has anyone else had this sort of issue? Any suggestions are greatly appreciated. thanks!