The car has manual climate control with air conditioning. The heat setting and blower control work as expected, however the vent control does not.

Setting it full floor does just that, same with full face or full defrost. However, the blended settings do not work correctly. With the "three-way" setting I can only feel a small amount of air coming out the floor vent, even with the blower on full. The "up-down" setting seems to result in air going nowhere. I can feel air leaking out of the center console, but it doesn't come out any vents. Same concept applies if I put the vent control between any of the major settings.

I'm not sure if it's coincidence or not, but the lights on my center stack also don't illuminate when the headlights are turned on.

A search of the archives didn't hit on anything as most "vent" threads involve engine issues, not HVAC. Any thoughts on where to go with this? At -5 deg F, I'd like to not have to choose whether my toes or torso get cold.

 

I have had intermittent issues with HVAC vents not letting the air come out where it's directed to. The problem has always resolved itself before I took action, though, so not much help, I'm afraid.

 

I'm a little afraid that it's the dreaded footwell module, but I can't find anything to confirm/deny that. I see other things ascribing electrical "gremlins" to an older battery, but I'm not sure if this falls into that sort of category or not. I don't like throwing parts/money at problems unless I'm more than reasonably certain of what the root of the issue is.