Defrost

1996 CHEVROLET 1500
140,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC
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ALEXT53
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When i turn my defrost on, it works on all parts except it does not blow out the driver windshield. So the entire car defrosts except the part i need to see out to drive. When i do turn it on high it makes a high pitch whining. I do not think its the actuator but i do not know. It is not stuck in defrost either.
Nov 15, 2017 at 11:02 AM
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STEVE W.
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Do you get any air out of the drivers defrost at all? High whine sounds like a blocked duct. It is one piece so if leaves or similar got in there and blocked it you would need to take out the dash to get the duct work out. If you look into the duct can you see anything?
Nov 16, 2017 at 2:37 PM
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ALEXT53
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There is no air coming out of the drivers defrost at all. I looked in there and there seems to be nothing blocking it or covering it.
Nov 17, 2017 at 8:01 AM
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STRAILER
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To me it sounds like the mode door actuator is not working but to be sure remove the actuator and then turn the system on and move the pivot back and forth to see if it makes a change and the defroster starts working.

Here isa guide to help see what I am talking about.

https://www.2carpros.com/articles/replace-blend-door-motor

Here is the location for your truck (below)

Please let us know what you find. We are interested to see what it is.

Cheers, Ken
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Nov 19, 2017 at 1:42 PM