Heat / Ac not working

[catlett73]

My fan switch no longer works on any speed, and the blower does not blow at all. I have replaced the blower motor and resistor, hvac control unit, checked fuses and even changed the blower relay. Nothing still works. I even hotwired the blower motor that I took out and the blower turned, so I now know that is not the issue. I am baffled as to what else it could be, and hope maybe someone else has had this issue on a 99 expy before. I have checked the current at all of the connections, and all have current where they should.

 

[stamp11127]

Is this an automatic climate control or manual controlled unit?

 

[catlett73]

this is a manual control unit

 

[stamp11127]

Your problem is standard electrical 101 trouble shooting. Watch this video to decided if you want to go further. If so you need to get a test light.

Using a test light to diagnose electrical problems - YouTube

How did you test the current? Did you have 12v at the blower resistor?