I have had both issues...blender actuator door malfunction and instrument cluster gauges malfunction. Guages seemed to correct themselves after disconnecting battery and discharging current (holding + and - electodes together for one minute). Blender door still malfunction. Will go by GM dealer toda...

I recently purchased a 2004 GMC Yukon. One morning the battery went dead. I jump started it with my Trailblazer. Then drove to NAPA, purchased and installed a new Group 78 battery (690 CCA). After installing the battery, I noticed that the driver's side A/C will now only blow hot air even though the...

Upon further online search, found this Technical Bulletin (carjunky.com) that seems to point to the "blend door" as the likely culprit. This appears to be a common problem with GM trucks and cars. My guess is that when the battery died, the car's computer some how screwed up the actuator s...

Oh yeah...one more thing. May be coincidence or unrelated, but battrry was dead when got up this morning to start truck (Yukon). Jump started. At time, ambient temps were cold..high30s/low 40s. Heater worked and running. Drove to local Napa and bought new battery. Replaced battery. By then temps wer...

What is the blender door?

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I am having the same problem with my 2004 GMC Yukon. Bought used 4 days ago. I am in South (Mississippi). Warm climate. I test drove vehicle on warm day (80 degree ambient temp) before purchasing and A/C worked fine. Blew cold. Yesterday temps dropped into 40s in morning. Ran car with heat. As temps...