my 98 camry air conditioning system only works through the vent, it won't blow out through the defroster or go to the floor
You have an inop blend door. The little flaps behind the dash are not actuating, that is why the air direction is only going one way. You will either have to live with it or take it to the shop. Usually the entire dash has to be torn apart to fix.
You might (repeat might) be able to access some mode doors through the glovebox or airbag opening. In some cases loosening the dash and inching it forward enough to get your hand back to the inoperative actuator can work. If the problem isn't the actuator but a broken/stuck door, then you'll be ripping out a dash. I've done a lot of them, it's mostly time consuming but not overly difficult.
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