have you been having intermittent issues prior to this or is this the first time you've seen any issues with this system?
can you change the fan speed? is the fan speed stuck on one setting?
can you redirect the vents?
can you put it in heat and heat comes out?
had any work done on the system? any other mechanical issues with the car? any work done on this system prior to this?
search the archives to get more info on others who have had similar issues (there may be some threads that might help you) but it could be an issue with the panel itself.
I just bought the truck & replaced VBR & the fan started blowing but the button worked for a brief moment when I first got the truck then it just stopped...other than that I don't see any serious mechanical issues...everything else works as it should
could be a fault then in the panel or perhaps there is not continuity in the wire harness. perhaps go back and eyeball your work and make sure all connecters and pins are tight and not loose or damaged. ive seen people replace something, post up that something else is not working, only to find out they didn't plug up something properly or something else end user related. not saying this is your issue, just to check things. otherwise, the panel could be faulty.