no rear air circulation from vents

We bought this 98 van a year ago and it has never had the roof vents working. The floor vent works and only for hot air. In the summer and the a/c NEEDS to be on, it only blows hot air back there (from floor only) if I turn the switch up front on. What are some possiblities for no a/c flow to the back at all, and no rooftops vents working?

I am having an electrical nightmare right now with that van anyway so I am just wanting to have some prior ideas or knowledge so when it comes to getting that fixed I may not be so ripped off ya know?

Thanks.

Jennifer

On the '98, the problem will like be pnematic..perhaps a hose leaking or blocked. The rear unit only has one blend door ... that acts for temperature and direction. Its a crazy scheme... but you only get heat@floor or cool@roof ... or a temp/flow-direction somewhere inbetween.

so it doesn't blow heat from roof only floor? And a/c from roof only right?
So then the problem lies then in the cool getting to the roof and it has only one line leading in so there must be a blockage or something right?

So it is probably a short in the wires that aren't allowing the vents to be opened so therefore nothing is going into them. Possibly? I see a lot of wires in the side by the middle row when taken out. Someone had spilled soda and it was all over in there and when we got the van I took it off to clean it, and saw the wires.
So possible that the previous owners' child shorted it out? Is the wire for that in the side at all?

Thanks

Jennifer

You've got the temp/direction (bad) idea correct...makes you proud to be a Ford owner don't it?

I would suggest you remove the LH rearmost inner-lower plastic trim panel ... and all will be revealed to you. I still suspect a pneumatic... not electric... problem.

OK. so is it possible to let me know what a pneumatic problem is, lol? Not sure what that means. Thank you for you help.

Jennifer

I THINK (based on postings by others) that, up thru '98, the rear blend door had a door "actuator" (motor) that was powered by vacuum from the engine intake manifold. The vacuum first goes to the controller switch on your instrument panel ... then on to the rear unit.
In '99+ these blend door actuators were changed to be powered by electricity. This I'm pretty sure of because I have a '99.
That's why I suggest you remove the trim panel that covers the rear ac/heater unit and you will be able to test the blend door by applying some vacuum directly ... (or electricity if I'm wrong about the vacuum).