i have no air flow through defrost and dashboard vents. how do i fix?


Asked by Apr 14, 2013 at 03:32 PM about the 1994 GMC Sierra 1500 C1500 SL Standard Cab SB

Question type: Maintenance & Repair

I have pulled most of the dashboard off in order to see the vent doors. it appears that the doors are working. no air coming out the dashboard or defrost vents. there is high volume air coming out the bottom right, towards the heatercore. i believe that one or more actuator motors need replacing. how do i determin witch ones to replace. any help would be grateful. thanks

3 Answers


Here's a basic HVAC flow diagram that might help.

9 out of 9 people think this is helpful.
Best Answer

thanks for the diagram. where can i get a print like this in a normal size to be able to read it. (bad eyes)

2 out of 2 people think this is helpful.

Click on the print - it will become full screen. Right click on the full size and copy it to your folder. Then click on that "Best answer" button.

3 out of 3 people think this is helpful.

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