I have a 1999 accord ex 4 cylinder automatic transmission, the blower motor only works on high. could it be the resistor motor?

 

Ive work on a person car who had the same problem. the air would only blow on high. I took out the ac control panel and inspected the contacts. four of the five contacts showed burn marks. i think i scraped the metal contacts to make a better contact and it worked fine. all 5 fan speeds worked.

 

Possibly it's like antec says, but when it only works on high-speed, that usually means the speed-control resistor is bad.