REPOST from main forum:

This morning the climate system in my '01 Explorer Sport was working perfectly.... until I jumped in for the commute home, which is when I noticed that the heater was not working.

I pulled over, restarted the car... still nothing. I tried the AC.... nothing.

I still hear the "clicks" under the hood when I switch it to AC or heat, but nothing happens. What should I try first before I take it into the garage because I can't handle another 22 degree drive home from work!!!

Thanks all!
:us:

exactly what is "nothing?" You mean it's not blowing any air? Or only cold air?

Have you tried all fan speeds? If not, see if it works on the highest setting only, or vice versa. A common problem is the resistor that controls the blower speed burning out. If it doesn't work in high but works in all other modes, you'll want to check the Hi Speed Blower Relay.

If the blower isn't turning at all you may need to check the fuse.