thead vehicle "door" control

Maybe someone can help with this
If I want my vehicl's door's to open when then vehicle spawns then close when ther person is mounted" I would

function VehicleThing::onAdd(){
Parent::0nAdd(%this, %obj);
//other code
[b]
%obj.schedule(5500, "playThread", $ActiveThread, "open_door");[/b]
}

then

function VehicleThing:playerMounted(%data, %obj, %player, %node){
//other code
//HERE I HAVE NO CLUE}

so it takes the sequence "open_door" and plays it till the end(assuming it is non cyclic)could someone explain the 5500 , im sure it deals with ticks or something.

What do I put in the schedule for on mounted? I found a referance to
bool setThreadDir(thread,bool);

so could it be
%obj.schedule(5500, "setThreadDir", $ActiveThread, ,"open_door", false);
if so how does it know which thread to use? someone please clarify?