My 1997 Civic LX has an issue where no matter the vent setting (feet only, defrost/feet, defrost only) the front vents are always blowing. I'm not talking about the little vents either that point to the driver/passenger door glass but the actual four outter and inner vents. When switching to non-front vent modes I do get what I select but it's always in addition to the front vents. I'm assuming it's a bad connection or board somewhere under the dash. Thanks!
I made a mistake as I double checked the operation of the vents and it turns out the middle vents do turn off when they're supposed to. I was under the impression the outter vents would turn off as well but they don't as they're tied directly to the mini-vents that point towards the driver or passenger window. I just closed the outer vents to direct more flow to the mini-vents. Thanks for the details though as maybe it may help someone in the future.
The vents are operated by cables which are connected to the lever controls behind the dash. They can become dis-connected at thier ends. A simple refit of the cable(s) may be all is required.