My heater switch works off and on. Is there a relay that might be weak? It will switch from Air to Defrost to Heat but fan doesn't always work. Has anyone install a separate switch to turn fan on and off ? My low speed of fan never worked. Maybe something I could mount under dash, also maybe two speed would be real nice. I have a wiring diagram but hard to read and understand. Thanks for any help.

 

can you see the color coded wires from the climate control module to the motor in your wiring diagram? if so, you might run power directly to the fan motor from the wiring harness connector to make sure it's not the problem or that there's not a wiring issue between the module and the motor. modules can be purchased rebuilt for around $300 from autohausaz.com or check ebaymotors.com for used.