My 1999 My blower fan works on one speed only. It will work on high and will not run in any other position. What can be causing this?

 

My guess would be the switch....

 

In my 06' the same thing happened it only worked on settings three and four but not one and two. I changed the resistor and everything works great now only cost me $30. Im not sure if its the same things with the 99' but it probably could be.

 

Just as "aPINCHbetter90" said your "Blower Motor Resistor" has burnt out.

 

My 99 I just bought has the same issue. Where is the Blower Motor Resister, if this is the root cause of the issue?

Regards,
Jeff