You'll probably have to take the dash apart. Check hondaautomotiveparts.com for some drawings of the heater controls & heater distribution box. But I think those pictures aren't real helpful until you get it apart.

I think there's one cable going from the control lever to a hot/cold mixing door lever. From there, a 2nd cable goes out to the valve. So there's a couple places where either cable might be disconnected.

This hot/cold mixing door is not the same as the air direction dampers which direct the air to the dash/defrost/floor/etc.