I have a hampton bay fan. The speed regulator is not working. It runs in full speed, then the other two are also going full, the last one just turns it off. It used to work earlier.

Is it a remote fan?

General ceiling fan troubleshooting and help FAQ- Ceiling Fans N More (http://www.ceiling-fans-n-more.com/ceiling-fan-general-troubleshooting-and-FAQ.php)