Well, all of a sudden (during a snowstorm actually) my HVAC will only blow through the face vents. I researched and found it's most likely the actuator motor. Although, it seems that everyone says that when it fails it defaults to the defrost setting (which is the opposite of mine).
So I got another one at auto zone, pulled the old one, and installed the new one. Problem is, when I change the settings the actuator only moves MAYBE 1/16" so not enough to actually engage the defrost. I removed the actuator and manually manipulated the little half wheel that moves the blend door, and it works fine. So I plugged the actuator in without installing it and cycled through the settings. It doesn't move but fractions of what it looks like it's supposed to be able to. Could it be the switch in the dash isn't sending the proper signals?
Also, when I searched the part number on the old unit on the AutoZone website, it came up with "cross-referenced" and gave me the part number of the replacement. Is it possible that this is the incorrect actuator? Also, while looking at the actuator and cycling the settings I noticed that going from full face, to face/floor the actuator did not move AT ALL. Going from face/floor to full floor it moved slightly. Moving from full floor to floor/defrost it did not move AT ALL. Then going from floor/defrost to full defrost it moved slightly.
Thanks
Sorry, it's a 2002 Yukon XL 2500 8.1
So I got another one at auto zone, pulled the old one, and installed the new one. Problem is, when I change the settings the actuator only moves MAYBE 1/16" so not enough to actually engage the defrost. I removed the actuator and manually manipulated the little half wheel that moves the blend door, and it works fine. So I plugged the actuator in without installing it and cycled through the settings. It doesn't move but fractions of what it looks like it's supposed to be able to. Could it be the switch in the dash isn't sending the proper signals?
Also, when I searched the part number on the old unit on the AutoZone website, it came up with "cross-referenced" and gave me the part number of the replacement. Is it possible that this is the incorrect actuator? Also, while looking at the actuator and cycling the settings I noticed that going from full face, to face/floor the actuator did not move AT ALL. Going from face/floor to full floor it moved slightly. Moving from full floor to floor/defrost it did not move AT ALL. Then going from floor/defrost to full defrost it moved slightly.
Thanks
Sorry, it's a 2002 Yukon XL 2500 8.1
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