How can I determine if the control panel is out on my 94 Accord or if it's the blend door servo that is out? My panel lights up and changes to all settings, EXCEPT for the "vent only" setting. Can the panel be out but still operate all other functions? Which ever it is, is there a step-by-step guide to follow to do it myself?

I did a search and it did not return the results I was looking for.

Thanks,
Shawn