My 2005 yukon has no ac blower fan control

SOURCE: 2005 Yukon XL, third brake light intermittent

Remove bulb, make sure it sits tight in the socket. make sure socket is not burnt up (brown or black in color) Check bulb, if the filament inside is loose or discolored, replace as nesessary. Check brake light switch under driver side dash above brake pedal. make sure it is adjusted correctly.

SOURCE: 99 Yukon - Blower Motor Not Working

replace the A/C control head... very simple to do. Pop off the dash panel and pull the control head out... unplug the 3 harnesses and there you go.

SOURCE: 99 Yukon - Blower Motor Not Working

If you have already changed the blower motor, than ignore my comment. My 99 Suburban blower didn't work on low speed, only medium high and high. I thought it was the resistor pack, so I changed it. The low speeds then worked, but I quickly noticed a burning smell at the two lowest speeds. I turned it off quick not to burn up the new resistor pack. I noticed one terminal of the fan switch wire connector looked to have gotten very hot in the past. I changed the fan switch but no change in symptoms. Still smelt like burning at low speeds. The motor appeared to work fine durning all this, but with nothing else to try we swapped out the motor for a new one and that sloved all the problems. The original motor was wearing out and though running fine was pulling to many amps through the fan switch and resistor pack. For those that haven't replaced the blower motor yet, I'd advise doing this as preventative maintaince so you don't burn up the resistor pack, fan switch, or wiring.

SOURCE: GMC Yukon Denali XL Auxiliary Blower Motor Battery Drain

Your new resistor should contain a built in relay. Sounds like that is sticking, swap the new part for another as it could be that you got a bummed replacement.

SOURCE: My 2005 Yukon AC blower is not blowing. THe

There is a service bulletin for this problem which replaces the blower resistor and connector. Mine had the same problem while on vacation. No fan speed control, and when it did work, the fan would keep running after the vehicle was shut off. Mine is currently in the shop getting the service bulletin installed.